Developer & DevOps for Developer

331 developer & devops tools hand-picked for Developer.

AI Eval Planner

Generate eval cases, pass criteria, and edge cases from an AI feature, risks, and user path.
API Key Generator

Generate cryptographically random API keys and secret tokens with a custom prefix, length, and charset, with a live entropy readout, entirely in your browser.
ASCII Table Generator

Paste CSV or TSV, get a monospace table that lines up: +--+ ASCII, Unicode box, Markdown, with real CJK width
ASCII Table Reference

Complete 0–127 ASCII table: decimal, hex, octal, binary, character, name, HTML entity and escape — control codes explained, click to copy, fully searchable.
awk + sed Cheatsheet

awk + sed cheat sheet — 80+ one-liners for text processing, with real examples and common pitfalls.
AWS CLI Cheatsheet

AWS CLI cheat sheet — 80+ commands for EC2 / S3 / IAM / Lambda / RDS / EKS / CloudFormation with real examples.
Barcode Generator

Code 128 / EAN-13 / UPC-A / Code 39 — generate scannable 1D barcodes, export SVG or PNG, fully offline.
Number Base Converter

Number base converter — binary, octal, decimal, hex, and any base 2-36. Bitwise too.
Base32 / Base58 Encoder & Decoder

Base32 + Base58 encoder/decoder — RFC 4648 base32 (Crockford variant too), Bitcoin base58, Solana base58, hex/text/file input.
Base62 Encoder & Decoder

Turn big integers and UTF-8 text into compact 0-9A-Za-z strings, the way short-URL services pack an ID into 6 characters, all in your browser
Base64 Block Deduplicator

Find duplicates and keep one clean copy of base64 blocks from pasted text or uploaded local files.
Base64 Block Extractor

Extract, dedupe, and export base64 blocks from pasted text or uploaded local files.
Base64 Block List Converter

Convert base64 blocks from pasted text or uploaded local files.
Base64 Block List Validator

Validate and explain issues in base64 blocks from pasted text or uploaded local files.
Base64 Block Normalizer

Normalize, sort, and prepare base64 blocks from pasted text or uploaded local files.
Base64 to File Converter

Paste raw Base64 or a data URL, decode it locally, inspect bytes, and download the reconstructed file.
Base64 to Hex Converter

Base64 ⇄ hexadecimal at the byte level, no text encoding in between — standard or URL-safe, your separator and case, runs in your browser
Bash Cheatsheet

Bash cheat sheet — 100+ commands & idioms for variables, conditionals, loops, functions, pipes, traps, with real one-liners.
Basic Auth Header Generator

Username plus password into Authorization Basic base64, with curl -u and -H examples, plus reverse decoding, all in your browser
Batch File Rename Planner

Upload a batch, generate safe new filenames with sequence numbers and case rules, then export a CSV plan.
Bcrypt Generator

bcrypt password hash generator + verifier — pick rounds, hash and compare in browser.
Bitwise Calculator

AND, OR, XOR, NOT and bit shifts on integers, with decimal, hex and binary side by side, all in your browser
CSS Border Radius Generator

Border radius generator — independent 8-corner control + blob shape randomizer, live preview, copy CSS or SVG path.
Cache-Control Builder

Tick the directives, set the lifetime, copy a correct Cache-Control header plus Nginx and Apache lines
Case Converter

Convert text between camelCase, snake_case, kebab-case, PascalCase, Title Case, UPPER, lower — instant, browser-only
Code Screenshot Generator

Code screenshot generator (Carbon-like) — syntax highlight, beautiful gradient backgrounds, window chrome, export PNG/SVG for X / blog covers.
Collatz Conjecture Calculator

Enter any positive integer, watch 3n+1 run to 1 — full hailstone sequence, stopping time, and peak, exact via BigInt
Color Blindness Simulator

Color blindness simulator — paste hex or upload image, see how it looks to people with protanopia / deuteranopia / tritanopia / monochromacy.
Color Contrast Checker

Color contrast checker — WCAG 2.2 AA/AAA compliance for normal/large text, real-time grade.
Color Converter

HEX ⇄ RGB ⇄ HSL ⇄ HSV ⇄ CMYK — instant 5-way conversion, live swatch — browser-only
Column Align

Pad delimited rows into an even monospace grid, like column -t, with correct CJK width — browser-only
Common Ports Reference

TCP/UDP port cheat sheet, 60+ services, search by number or name, copy in one click, browser-only
CORS Header Generator

Pick an origin, methods and headers, get Access-Control-* response headers as a raw list, Nginx, Apache or Express code
CRC32 Checksum Calculator

Standard CRC-32 (IEEE) of any text in hex and unsigned decimal, with optional CRC32C, computed in your browser
Credit Card Number Deduplicator

Find duplicates and keep one clean copy of credit card numbers from pasted text or uploaded local files.
Credit Card Number Extractor

Extract, dedupe, and export credit card numbers from pasted text or uploaded local files.
Credit Card Number List Converter

Convert credit card numbers from pasted text or uploaded local files.
Credit Card Number List Validator

Validate and explain issues in credit card numbers from pasted text or uploaded local files.
Credit Card Number Normalizer

Normalize, sort, and prepare credit card numbers from pasted text or uploaded local files.
Test Credit Card Number Generator

Luhn-valid fake card numbers for payment-integration testing — Visa, Mastercard, Amex, Discover, JCB, Diners — non-real, sandbox-only — browser-side
Cron Expression Explainer — Decode Any Cron + Next 20 Runs

Cron expression explainer — paste any cron, get plain English/Chinese + next 20 runs + visual time grid.
Crontab Helper — Visual Builder & Explainer

Visual crontab builder + human-readable explanation + next run preview.
CSP Generator

Build a Content-Security-Policy from directive toggles, get the header line, meta tag and Nginx snippet, with live unsafe-inline warnings, browser-only
CSP Policy Auditor

Inspect Content-Security-Policy directives for unsafe sources, missing fallbacks, framing gaps, object-src, base-uri, and reporting coverage.
CSS Button Generator

Design buttons that look pressable — 3D raised, neumorphic, glass — with a live preview you can hover & press, plus full :hover/:active CSS export
CSS clamp() Fluid Typography Generator

CSS clamp() fluid typography generator — min/max font size, viewport range, full type scale (h1-h6 + body), copy CSS / Tailwind.
CSS Filter Generator

Dial in blur, brightness, contrast, grayscale, sepia, hue-rotate, saturate, invert, opacity + drop-shadow with live preview — copy the filter string
CSS Font Stack Generator

CSS font stack generator — system-safe font families with full Win/Mac/Linux/Android/iOS fallback chains, with CJK fallbacks, copy as CSS/Tailwind/SwiftUI.
CSS Formatter & Minifier

Format and beautify CSS — sort properties, indent rules, expand or minify.
CSS Grid Visual Generator

CSS grid visual generator — drag to set columns/rows, place grid-area named regions, copy ready CSS + HTML, with 12 layout templates.
CSS Grid Generator

CSS Grid generator — visually design grid layouts (rows/cols/gap/areas), copy CSS code, fully responsive.
CSS Keyframes Animation Generator

Visually build @keyframes — edit keyframes, set transform/opacity/color, live-preview, and copy production-ready CSS — browser-only
CSS Media Query Generator

CSS @media query + responsive breakpoint generator — Tailwind / Bootstrap / Material presets, mobile-first vs desktop-first, dark mode, hover, reduced-motion, aspect-ratio.
CSS Minifier

Minify CSS — strip comments, whitespace, shorten colors, merge selectors. 30-60% smaller.
CSS Scrollbar Generator

Design custom scrollbars visually — exports WebKit + Firefox-standard CSS, live preview, one-click copy — browser-only
CSS Specificity Calculator

Score any CSS selector as an (a, b, c) triple, compare which rule wins the cascade, and see exactly which digit decided it — browser-only
CSS to Style Object

Paste CSS declarations, get a React inline style object — kebab keys camelCased, vendor prefixes handled, optional bare numbers, browser-only
CSS Transform Generator

CSS transform generator — rotate/scale/skew/translate (2D + 3D) with live preview, copy CSS, 12 preset combos.
CSS Triangle Generator

Pure-CSS triangles via the border trick — 8 directions, live preview, copy both border + clip-path CSS — browser-only
CSS Variable Deduplicator

Find duplicates and keep one clean copy of css variables from pasted text or uploaded local files.
CSS Variable Extractor

Extract, dedupe, and export css variables from pasted text or uploaded local files.
CSS Variable List Converter

Convert css variables from pasted text or uploaded local files.
CSS Variable List Validator

Validate and explain issues in css variables from pasted text or uploaded local files.
CSS Variable Normalizer

Normalize, sort, and prepare css variables from pasted text or uploaded local files.
CSV Column Extractor

Upload or paste CSV, keep only selected columns by name or index, and export a smaller privacy-safe file.
CSV Data Quality Profiler

Upload CSV or TSV and profile missing values, inferred types, invalid cells, duplicate rows, whitespace issues, top values, and numeric outliers.
CSV Deduplicator

Remove duplicate CSV rows by full row or selected key columns from uploaded files, locally and safely.
CSV Filter

Filter uploaded CSV rows by column value using contains, equals, or regex, with local browser processing.
CSV Header Normalizer

Standardize CSV header rows to snake_case, kebab-case, camelCase, or Title Case before imports and scripts.
CSV Sorter

Sort uploaded CSV rows by a selected column with numeric-aware ordering and local-only processing.
CSV Stats Summary

Upload CSV and get a quick Markdown profile of filled, missing, unique, numeric, min, max, and average values.
CSV ⇄ JSON Converter

Convert CSV to JSON or JSON to CSV — handles quoted commas, newlines in cells, custom delimiter — browser-only
CSV to Markdown Table

Convert uploaded or pasted CSV into clean Markdown tables with quoted-cell support, locally in the browser.
CSV to SQL Converter

Turn CSV into CREATE TABLE + INSERT statements — type inference, safe value escaping, MySQL / PostgreSQL / SQLite — browser-only
CSV to TSV Converter

Convert CSV files to tab-separated values while preserving quoted commas, quotes, and multiline cells locally.
CSV to XML Converter

Turn a CSV table into clean, indented XML — name the root and row elements, columns as elements or attributes, escaped output. Browser-only.
CSV to YAML Converter

Turn a spreadsheet export into a clean YAML array of objects — RFC 4180 quoting, optional type inference, browser-only
CSV Transposer

Flip CSV rows and columns from uploaded files or pasted data, with ragged-row handling and local output.
Cubic Bezier Editor

CSS cubic-bezier editor — drag two control points, preview live with bouncing ball + scaling box + opacity fade, copy CSS / JS / Framer Motion / GSAP / SVG path.
curl Cheatsheet

curl cheat sheet — 80+ curl commands for GET/POST/auth/upload/download/SSL/proxy, with real examples and pitfalls.
curl to Code Converter

Paste a curl command, get JS fetch / Python requests / Node axios / PHP cURL / Go net/http — parsed locally, instant
DNS Record Explainer

DNS record explainer — all 18 common record types (A, AAAA, CNAME, MX, TXT, SRV, etc.) with syntax, examples, and gotchas.
Docker Cheatsheet

Docker command cheat sheet — 80+ commands with real examples, common mistakes, and Compose section.
Domain Name Deduplicator

Find duplicates and keep one clean copy of domain names from pasted text or uploaded local files.
Domain Name Extractor

Extract, dedupe, and export domain names from pasted text or uploaded local files.
Domain Name List Converter

Convert domain names from pasted text or uploaded local files.
Domain Name List Validator

Validate and explain issues in domain names from pasted text or uploaded local files.
Domain Name Normalizer

Normalize, sort, and prepare domain names from pasted text or uploaded local files.
.env File Validator

.env file validator — parse Bash-style .env, detect dups / missing required / unsafe values / leaked secret patterns; cross-compare prod / staging / dev envs.
Duplicate File Finder

Upload a batch and find exact duplicate files by SHA hash locally, with a Markdown cleanup report.
.editorconfig Generator

Visual .editorconfig builder — indent, charset, line endings, trailing whitespace, per-glob overrides — browser-only
Elasticsearch Cheatsheet

Elasticsearch cheat sheet — 80+ Query DSL, mapping, analyzer, aggregation, replication, with real examples.
Email Address Deduplicator

Find duplicates and keep one clean copy of email addresses from pasted text or uploaded local files.
Email Address Extractor

Extract, dedupe, and export email addresses from pasted text or uploaded local files.
Email Address List Converter

Convert email addresses from pasted text or uploaded local files.
Email Address List Validator

Validate and explain issues in email addresses from pasted text or uploaded local files.
Email Address Normalizer

Normalize, sort, and prepare email addresses from pasted text or uploaded local files.
Email Obfuscator

Hide your email from scraper bots — HTML entities, [at]/[dot] text, ROT13+JS link — browser-only, one-click copy
Email Signature Generator

Fill in your details, pick a template, get table-based inline-style HTML that pastes cleanly into Gmail and Outlook — 100% browser-only
Email Validator

Validate emails — RFC 5321 syntax + bulk paste + disposable detection + MX hint.
Emoji to Unicode Converter

Emoji ⇄ Unicode code points, both ways. U+XXXX, decimal, HTML entity, JS and CSS escapes, every code point of a ZWJ family, skin tone or flag, plus one-click restore, all in your browser
ENV Secret Scanner

Scan .env files, config snippets, and CI logs locally for likely API keys, tokens, private keys, JWTs, and database URLs.
.env to JSON Converter

Convert .env environment variables to JSON and back, with quote escaping, export prefix, and optional type inference, all in your browser
Environment Variable Deduplicator

Find duplicates and keep one clean copy of environment variables from pasted text or uploaded local files.
Environment Variable Extractor

Extract, dedupe, and export environment variables from pasted text or uploaded local files.
Environment Variable List Converter

Convert environment variables from pasted text or uploaded local files.
Environment Variable List Validator

Validate and explain issues in environment variables from pasted text or uploaded local files.
Environment Variable Normalizer

Normalize, sort, and prepare environment variables from pasted text or uploaded local files.
Fibonacci Generator

First N terms, a range, or the nth value, with running sum and golden-ratio convergence, exact via BigInt, all in your browser
File Checksum Compare

Paste an expected checksum, upload a file, and verify SHA digest matches locally before installing or sharing.
File Hash Calculator

Compute SHA-1, SHA-256, SHA-384, or SHA-512 hashes for uploaded files entirely in the browser.
File MIME Type Inspector

Upload files and inspect filename, size, browser MIME type, extension, and magic-byte signature locally.
File to Base64 Converter

Upload a small file and convert it to raw Base64 or a data URL locally for embeds, fixtures, and tests.
Filename Sanitizer

Strip illegal characters and make any string a safe cross-platform filename, in your browser
Find and Replace Text

Batch find-and-replace on big text — regex, $1 capture groups, whole-word, case toggle, multiple chained rules — runs entirely in your browser
Flexbox Playground & CSS Generator

Flexbox playground — toggle every container and item property on a real flex box and copy the exact CSS. direction, justify, align, gap, order, grow/shrink/basis, align-self. 100% client-side.
Font File Inspector

Upload TTF or OTF files and extract family names, PostScript names, version, units per em, glyph count, and table list.
Git Cheatsheet

Git command cheat sheet — searchable, with explanations, common mistakes, and real examples.
GitHub README Badge Generator

GitHub README badge generator — shields.io-style badges, 50+ presets (build/version/license/coverage/etc), custom labels, copy as Markdown/HTML/AsciiDoc/RST.
.gitignore Generator

Pick your stack — Node, Python, Go, Docker, macOS, VS Code — and get a deduped, sectioned .gitignore. Browser-only.
Go (Golang) Cheatsheet

Go (Golang) cheat sheet — 100+ idiomatic snippets covering syntax, goroutines, channels, generics, errors, stdlib.
GraphQL Formatter & Minifier

GraphQL formatter + minifier — beautify query/mutation/subscription/schema, validate syntax, copy minified single-line for HTTP body.
Gray Code Converter

Decimal, binary and Gray code three ways, gray = n^(n>>1), one click each side, all in your browser
gron Converter (JSON to gron / ungron)

Make JSON greppable. json.users[0].name = "Ada"; one leaf per line, and ungron right back. Runs in your browser.
Hamming Distance Calculator

Count the differing positions between two equal-length inputs, in characters, binary bits or integer XOR, all in your browser
HAR Performance Analyzer

Upload a Chrome DevTools HAR file and get a local performance, cache, host, asset, status, and security-header report.
Hex Dump Viewer

Offset, hex bytes and ASCII side by side, the classic xxd / hexdump -C layout, fully in your browser
HMAC Generator

HMAC-SHA1/256/384/512 — message + secret key, output in hex and base64, key read as UTF-8/hex/base64 — 100% in-browser
.htaccess Generator

Generate Apache .htaccess — HTTPS redirect, www toggle, gzip, cache headers, hotlink protection.
HTML Color Names

HTML named colors — all 147 CSS color names with hex/RGB/HSL, searchable + sortable.
HTML Entities Encoder

Encode/decode HTML entities — & < > " ' and all numeric refs — browser-only
HTML Form Extractor

Upload or paste HTML and extract forms, methods, actions, fields, labels, required flags, autocomplete, password fields, and security risks.
HTML Formatter

Beautify minified or messy HTML into clean indented markup, browser-only
HTML Link Extractor

Upload HTML and extract anchors, images, scripts, stylesheets, canonicals, and meta URLs into CSV locally.
HTML Minifier

Minify HTML — strip comments, whitespace, optional attributes, inline CSS/JS. 40-60% smaller.
HTML Table Generator

Build an HTML table visually — rows/columns, header cells, alignment, borders, zebra stripes, paste CSV/TSV — copy clean markup, browser-only
HTML Table to CSV Converter

HTML table to CSV converter — paste HTML or full page source, extract all tables, get CSV/TSV/JSON/Excel-ready output with header detection + colspan/rowspan handling.
HTML Table to JSON

Paste an HTML <table>, get clean JSON, array of objects or 2D array, type inference, browser-only
HTML Table to Markdown

Paste an HTML table, get a clean GitHub-flavoured Markdown table with the |---| separator row, tags stripped, entities decoded and pipes escaped, all in your browser
HTML to JSX

Paste HTML, get React-ready JSX — class becomes className, inline styles become objects, tags self-close. Browser-only.
HTML to Markdown

HTML to Markdown — paste rich content, get clean .md with links, code, tables, lists preserved.
.htpasswd Generator

Generate Apache/Nginx .htpasswd lines — bcrypt, apr1 (MD5), SHA-1 — multi-user, copy, download — 100% browser-only
HTTP Header Deduplicator

Find duplicates and keep one clean copy of http headers from pasted text or uploaded local files.
HTTP Header Extractor

Extract, dedupe, and export http headers from pasted text or uploaded local files.
HTTP Header List Converter

Convert http headers from pasted text or uploaded local files.
HTTP Header List Validator

Validate and explain issues in http headers from pasted text or uploaded local files.
HTTP Header Normalizer

Normalize, sort, and prepare http headers from pasted text or uploaded local files.
HTTP Security Header Auditor

Audit raw response headers for HSTS, CSP, cookie flags, MIME sniffing, clickjacking, referrer, and permissions policy gaps.
HTTP Status Code Explorer

HTTP status code explorer — all 70+ codes with meaning, common causes, real examples, and what to check.
IBAN Validator

Check any IBAN with the ISO 7064 mod-97 checksum and a 60-country length table, formatted output, one-click copy, browser-only
Image Compressor (Local)

Image compressor — squeeze JPG/PNG/WebP without server upload, with quality slider, batch mode, file size comparison.
Image Metadata Inspector

Inspect PNG, JPEG, GIF, WebP, and SVG dimensions, bit depth, ICC, EXIF, XMP, animation, and notes.
INI Formatter & Validator

Format and validate INI / TOML-like config — sort sections, align equal signs.
INI to JSON Converter

Turn INI / .cfg / .conf into JSON and back, with section nesting, comment stripping and optional type inference, all in your browser
IP Subnet Calculator (CIDR)

Type an IPv4 CIDR and get network, broadcast, host range, mask, wildcard, class and subnet splits — browser-only.
IP to Decimal Converter

IPv4 dotted-quad to 32-bit integer, binary and hex, both directions, browser-only
IPv4 Address Deduplicator

Find duplicates and keep one clean copy of ipv4 addresses from pasted text or uploaded local files.
IPv4 Address Extractor

Extract, dedupe, and export ipv4 addresses from pasted text or uploaded local files.
IPv4 Address List Converter

Convert ipv4 addresses from pasted text or uploaded local files.
IPv4 Address List Validator

Validate and explain issues in ipv4 addresses from pasted text or uploaded local files.
IPv4 Address Normalizer

Normalize, sort, and prepare ipv4 addresses from pasted text or uploaded local files.
IPv6 Address Deduplicator

Find duplicates and keep one clean copy of ipv6 addresses from pasted text or uploaded local files.
IPv6 Address Extractor

Extract, dedupe, and export ipv6 addresses from pasted text or uploaded local files.
IPv6 Address List Converter

Convert ipv6 addresses from pasted text or uploaded local files.
IPv6 Address List Validator

Validate and explain issues in ipv6 addresses from pasted text or uploaded local files.
IPv6 Address Normalizer

Normalize, sort, and prepare ipv6 addresses from pasted text or uploaded local files.
ISBN Validator

Check an ISBN-10 or ISBN-13 check digit and convert between the two, with the X case and 978 prefix handled, all in your browser
JS Minifier

Minify JavaScript — strip comments, whitespace, optional name shortening. 40-70% smaller.
JS Obfuscator

Lightly obfuscate JavaScript in the browser: strip comments, remove debugger/console calls, and optionally wrap strings with base64.
JS Object to JSON

Paste a JS object literal or JSON5, get strict JSON: quote bare keys, swap single quotes, strip comments and trailing commas, runs in your browser
JSON Diff

Structural JSON compare — added / removed / changed keys by path, three-colour tree, browser-only
JSON Flatten / Unflatten

Flatten nested JSON to dot-notation keys and unflatten it back — choose the delimiter and array style, types preserved, browser-only.
JSON Formatter & Validator

Format, validate, and minify JSON instantly — right in your browser.
JSON-LD Schema Generator

Build valid schema.org JSON-LD for Article, Product, FAQ, LocalBusiness, Event and more, copy the script tag, drop it in your head
JSON Lines Formatter

Validate JSONL line by line, pretty-print it, convert to a JSON array, or export a CSV-like table locally.
JSON Minifier

Minify JSON into a compact single line, optionally sort object keys, and keep everything local.
JSON Schema Inferencer

Paste JSON or NDJSON samples and infer a Draft 2020-12 style schema with types, required fields, formats, enums, and examples.
JSON Sort Keys

Sort JSON object keys alphabetically, recurse into nested objects, asc or desc, values untouched, runs in your browser
JSON to C# Class

JSON to C# class or record — paste JSON, get PascalCase properties with System.Text.Json or Newtonsoft attributes, nested classes, nullable T?, init setters, DateTime detection.
JSON to CSV Converter

Turn a JSON array (or object) into clean CSV — flattens nested keys, escapes per RFC 4180, custom delimiter, UTF-8 BOM for Excel — browser-only
JSON to Dart Class

JSON to Dart / Flutter class — paste JSON, get final fields, camelCase names, factory fromJson, toJson, null-safe T?, nested classes, and optional @JsonSerializable codegen.
JSON to Go Struct

JSON to Go struct — paste JSON, get typed structs with json tags, exported fields, nested sub-structs, pointers for nullable, int64 and omitempty options.
JSON to Java Class

JSON to Java POJO, record, or Lombok @Data — paste JSON, get camelCase fields with getters/setters, Jackson @JsonProperty or Gson @SerializedName, nested classes, primitive vs boxed inference.
JSON to Kotlin Data Class

JSON to Kotlin data class — paste JSON, get val properties, camelCase fields, nullable T?, nested classes, and kotlinx.serialization @SerialName, Gson @SerializedName, or Moshi @Json annotations.
JSON to Markdown Table

Paste a JSON array of objects, get a clean GitHub-flavored Markdown table. Key union, pipe escaping, alignment, all in your browser.
JSON to PHP Array

JSON to PHP array — paste JSON, get a clean associative or indexed array with short [] or array() syntax, 2/4 indent, trailing comma, and an optional <?php return …; wrapper.
JSON to Protobuf

JSON to Protobuf — paste JSON, get proto3 message definitions with inferred scalar types, incrementing field numbers, snake_case fields, repeated arrays, and named nested messages.
JSON to Python Dataclass

JSON to Python — paste JSON, get @dataclass or Pydantic v2 models with type hints, Optional inference, nested classes, snake_case fields and aliases.
JSON to Query String Converter

Turn a JSON object into a URL query string — repeat, key[], or comma arrays, bracket-nested objects, sorted, skip-empty — and back to JSON, 100% in your browser
JSON to Rust Struct

JSON to Rust struct — paste JSON, get serde-derived structs with snake_case fields, serde rename, Option for nullable, Vec for arrays, nested sub-structs.
JSON to Scala

Paste JSON, get Scala case classes. Nested objects become child classes, arrays become List, null becomes Option, all in your browser.
JSON to SQL Converter

Turn a JSON array into ready-to-run INSERT statements, MySQL / PostgreSQL / SQLite dialects, browser-only
JSON to Swift Codable

JSON to Swift Codable — paste JSON, get struct or class types conforming to Codable, camelCase properties, a CodingKeys enum for non-matching keys, Optional T? for nullable fields, and nested types.
JSON to TSV Converter

Turn a JSON array into tab-separated values you can paste straight into Excel or Google Sheets, with header toggle and safe escaping, all in your browser
JSON to TypeScript Interface

JSON to TypeScript interface — paste JSON, get clean interfaces with union types from arrays, optional vs required detection, root name customizable.
JSON to XML Converter

Convert JSON to clean, indented XML — @attr/#text conventions, custom root, escaped output. Browser-only.
JSON to YAML Converter

Convert JSON to clean YAML — block scalars for multiline strings, optional key sorting, 2/4-space indent, line-numbered errors — browser-only
JSONL to JSON Converter

Turn newline-delimited JSON into a JSON array and back, with bad-line numbers and pick-your-indent — browser only
JSONPath / JMESPath Query Tester

JSONPath / JMESPath query tester — paste JSON, write a path, see matched values + matched paths highlighted live.
JWT Decoder

Decode JWT header / payload / signature — verify structure, check exp, copy claims — browser-only
JWT Encoder

Encode JWT — pick algorithm (HS256/HS384/HS512), set header/payload/secret, get token.
JWT Token Deduplicator

Find duplicates and keep one clean copy of jwt tokens from pasted text or uploaded local files.
JWT Token Extractor

Extract, dedupe, and export jwt tokens from pasted text or uploaded local files.
JWT Token List Converter

Convert jwt tokens from pasted text or uploaded local files.
JWT Token List Validator

Validate and explain issues in jwt tokens from pasted text or uploaded local files.
JWT Token Normalizer

Normalize, sort, and prepare jwt tokens from pasted text or uploaded local files.
kubectl Cheatsheet

kubectl cheat sheet — 100+ Kubernetes commands with real examples, common pitfalls, and YAML snippets.
Linux Permission (chmod) Calculator

Linux permission (chmod) calculator — convert between octal (755), symbolic (rwxr-xr-x), and ls -l forms, with safety warnings.
List Comparison

Compare two lists line by line: only in A, only in B, in both, and merged — all in your browser
List to JSON Array

Turn a column of lines into a JSON array, with type inference, dedupe and pretty print, and split it back to lines, all in your browser
LLM Pricing Calculator

Estimate daily and monthly LLM spend from tokens, request volume, and editable model prices.
Local File Workbench

Triage a mixed batch locally for file type mismatches, duplicate candidates, metadata privacy, archive risks, and next-step tools.
Log Error Analyzer

Paste logs and group repeated errors, warnings, stack traces, HTTP statuses, endpoint patterns, and time ranges into a local incident report.
Log Line Cleaner

Clean noisy logs by removing timestamps, ANSI colors, blank lines, long lines, or non-error entries in your browser.
Luhn Validator

Check any number against the Luhn (mod 10) algorithm, see the doubling math step by step, or compute the missing check digit, all in your browser
MAC Address Deduplicator

Find duplicates and keep one clean copy of mac addresses from pasted text or uploaded local files.
MAC Address Extractor

Extract, dedupe, and export mac addresses from pasted text or uploaded local files.
MAC Address Generator

Random MAC addresses in colon, hyphen, Cisco dotted or bare hex, with locally-administered and unicast bits and optional vendor OUI, all in your browser
MAC Address List Converter

Convert mac addresses from pasted text or uploaded local files.
MAC Address List Validator

Validate and explain issues in mac addresses from pasted text or uploaded local files.
MAC Address Normalizer

Normalize, sort, and prepare mac addresses from pasted text or uploaded local files.
Markdown Cheat Sheet

Markdown syntax cheat sheet — every rule with live preview side by side, GFM + flavors.
Markdown Editor with Live Preview

Markdown editor with live split-pane preview — GFM tables, fenced code with syntax highlight, math, emoji, table of contents, export as HTML / PDF-ready.
Markdown Link Extractor

Upload Markdown and extract inline links, reference links, images, and bare URLs into a local CSV.
Markdown Table Generator

Build Markdown tables visually — add/remove rows, column alignment, paste from Excel / CSV — browser-only
Markdown to Confluence Converter

Paste Markdown, get Confluence wiki markup — h1. headings, {code} panels, ||tables|| and {quote} blocks, all in your browser
Markdown to HTML

Convert Markdown to clean HTML — headings, lists, code, links, images, tables — instant live preview, browser-only
Markdown to Jira

Paste GitHub-flavored Markdown, get Jira wiki markup back — headings, bold, code blocks, tables, links, all in your browser
Markdown to JSX

Turn Markdown into React-ready JSX — one paste from README to a real component, with class becoming className and code blocks intact. Browser-only.
Markdown to reStructuredText

Convert Markdown to RST for Sphinx and Python docs, with matched heading underlines, double-backtick code and `text <url>`_ links, in the browser
Markdown to Slack

Paste standard Markdown, get Slack mrkdwn back: single-star bold, underscore italic, single-tilde strike, angle-bracket links, all in your browser
Markdown to Textile

Paste GitHub-flavored Markdown, get Textile markup back for Redmine and wikis, with headings, bold, code blocks, links and images converted in your browser
MD5 / SHA Hash Generator

Compute MD5 / SHA-1 / SHA-256 / SHA-384 / SHA-512 hashes — all five at once, browser-only
Meta Tag Generator

Generate SEO meta tags — title, description, Open Graph, Twitter Card, Schema.org.
MIME Type Lookup

File extension ⇄ MIME type lookup — 130+ types, both directions, copy the exact Content-Type — browser-only
Mock Data Generator

Generate realistic mock JSON / CSV / SQL data — names, emails, dates, addresses, nested objects.
MongoDB Cheatsheet

MongoDB cheat sheet — 80+ shell commands & query operators for CRUD, aggregation, indexing, replication.
NanoID Generator

Generate URL-safe NanoIDs with a custom alphabet, adjustable length, and a live collision-probability readout — entirely in your browser.
Next.js Cheatsheet

Next.js 15 cheat sheet — App Router, Server Components, Server Actions, dynamic routes, with examples and pitfalls.
Nginx Cheatsheet

Nginx cheat sheet — common configs, location/server blocks, SSL, reverse proxy, gzip, real examples & gotchas.
npm / yarn / pnpm Cheatsheet

npm / yarn / pnpm cheat sheet — 80+ commands across init, install, scripts, publish, with cross-tool comparison.
Number Extractor

Pull every number out of any text: integers, decimals, negatives, 1,234 commas, percents and 6.02e23, with instant sum and average
Number Sequence Generator

Generate a list of numbers from start to end by step or count, with zero-padding, prefix, suffix and any separator, all in your browser
Open Graph & Social Card Preview

See your og:title, og:image and twitter:card exactly as Google, X, Facebook, LinkedIn, Slack and Discord will render them — before you ship.
OpenAPI Endpoint Auditor

Audit OpenAPI JSON or YAML for endpoint coverage, missing operation IDs, security gaps, and weak response documentation.
Package Lock Dependency Auditor

Inspect package-lock.json, pnpm-lock.yaml, or yarn.lock for duplicate versions, risky sources, prereleases, and missing integrity.
Password Entropy Calculator

Entropy in bits, full character pool, and brute-force crack time across four attacker speeds, computed locally in your browser
Password Strength Checker

Check password strength — entropy, time-to-crack, breach pattern check (offline).
PDF Metadata Extractor

Upload PDFs and extract document metadata, page-count hints, encryption flags, and producer details locally.
PostgreSQL Cheatsheet

PostgreSQL cheat sheet — 80+ commands & functions for psql, JSONB, CTEs, window functions, indexing, partitioning, advanced extensions.
Properties ⇄ JSON Converter

Java/Spring .properties to JSON and back, with dotted-key nesting, line continuations and full escape handling, all in your browser
Punycode / IDN Converter

Unicode ⇄ Punycode for internationalized domains — münchen.de ⇄ xn--mnchen-3ya.de — per-label, email-aware, browser-only
PX REM EM Converter

CSS px ↔ rem ↔ em converter — visual scale, base font size adjustable.
Python Cheatsheet

Python cheat sheet — 100+ idiomatic Python snippets for string, list, dict, file, async, with real examples.
QR Code Decoder

QR code decoder — drag a QR image or paste URL, see the text/URL inside, plus phishing & risky-link warnings.
Batch QR Code Decoder

Drop a folder of QR images and get every decoded URL in one table — fast batch audit for packaging, posters, and print runs.
Query String to JSON Converter

Parse a URL query string into JSON and rebuild a query string from JSON — two-way, live, with array + nested object conventions — 100% in your browser
Quoted-Printable Encoder / Decoder

Quoted-Printable encode and decode by UTF-8 bytes, the way email MIME does it, with =XX escapes, trailing-space handling and 76-column soft wraps, all in your browser
React Hooks Cheatsheet

React hooks cheat sheet — all 17 built-in hooks (useState / useEffect / useMemo / useTransition / useFormStatus...) with real examples and pitfalls.
Redis Cheatsheet

Redis cheat sheet — 80+ commands across strings, hashes, lists, sets, sorted sets, pub/sub, streams, scripts, with examples and pitfalls.
Regex Builder from Examples

Regex from examples — paste positive matches + negative non-matches, get a regex that hits all positives and rejects all negatives, with multiple candidate patterns ranked by specificity.
Regex Cheatsheet

Interactive regex cheat sheet — quick reference for every flavor (JS, Python, PCRE).
Regex Escape

Turn literal text into a safe regex pattern: a.b becomes a\.b, copy the ready /…/ form, reverse it too, all in your browser
Regex Match Extractor

Pull every regex match out of any text, grab a single capture group, dedupe, one per line, copy in one click, all in the browser
Regex Tester

Test JavaScript regex live — match highlighting, group capture, replace preview, flag toggles — browser-only
Regex Visualizer

Regex visualizer — see your pattern as a railroad diagram + matching state machine, with capture groups highlighted.
Robots.txt Auditor

Check robots.txt for user-agent groups, allow and disallow rules, sitemap declarations, crawl-delay, and unsupported directives.
robots.txt Generator

Generate robots.txt with templates for common crawlers (Google, Bing, AI scrapers).
Rust Cheatsheet

Rust cheat sheet — 100+ snippets covering ownership, borrowing, lifetimes, traits, async, error handling.
Semantic Version Deduplicator

Find duplicates and keep one clean copy of semantic versions from pasted text or uploaded local files.
Semantic Version Extractor

Extract, dedupe, and export semantic versions from pasted text or uploaded local files.
Semantic Version List Converter

Convert semantic versions from pasted text or uploaded local files.
Semantic Version List Validator

Validate and explain issues in semantic versions from pasted text or uploaded local files.
Semantic Version Normalizer

Normalize, sort, and prepare semantic versions from pasted text or uploaded local files.
Semver Compare

Tell which semantic version is newer, sort a whole list, and check ^ ~ >= ranges, all in the browser
Shell Escape

Quote any string for bash safely: single-quote wrap, double-quote escape, backslash mode, and reverse, all in your browser
Sitemap URL Auditor

Paste sitemap XML and audit URL count, HTTP links, duplicates, trailing-slash conflicts, query parameters, lastmod freshness, and extensions.
URL Slug Generator

Turn any title into a clean URL slug — lowercase, dashes, ASCII-safe transliteration, multiline batch — browser-only
SQL Cheatsheet

SQL cheat sheet — 100+ statements covering SELECT, JOIN, window functions, indexing, MySQL/PostgreSQL/SQLite differences.
SQL Formatter

Format and beautify SQL — supports MySQL, PostgreSQL, BigQuery, SQLite and 17 more dialects.
SQL Minifier

Strip comments and whitespace from SQL — collapse to one compact line, string literals stay untouched, runs entirely in your browser.
String Escape / Unescape

Escape & unescape strings for JSON, JS, Java, C, SQL, Shell, HTML, CSV & regex — both directions — browser-only
String Similarity Checker

Levenshtein edit distance, Dice, Jaro-Winkler and LCS side by side, with a 0-100% match score, all in your browser
Svelte Cheatsheet

Svelte 5 cheat sheet — runes ($state, $derived, $effect), snippets, props, stores, with Svelte 4 comparison.
SVG Asset Auditor

Audit SVG viewBox, dimensions, scripts, external references, styles, ids, classes, title, and desc tags.
SVG Optimizer

SVG optimizer — strip comments/metadata/empty attributes, round path decimals, collapse useless groups, minify in browser. No upload.
SVG to Data URI / CSS Background

Inline any SVG as a data URI — URL-encoded (smaller) or base64 — with ready-to-paste CSS, HTML and bare-URI output, side-by-side size diff, 100% in-browser.
SVG to JSX

Paste SVG, get a React component — attributes camelCase, style becomes an object, wrap with {...props} passthrough. Browser-only.
Tabs to Spaces Converter

Convert tabs to spaces and spaces to tabs, real tab-stop alignment, leading-indent or whole-line, all in your browser
Tailwind CSS Cheatsheet

Tailwind CSS cheat sheet — 100+ utility classes (spacing, color, flex, grid, typography, responsive) with live preview.
Text Diff

Compare two blocks of text — line-by-line additions, deletions, equal — colour highlighted, browser-only
Text File Cleaner

Upload a text file and remove BOM, null bytes, trailing spaces, and excessive final blank lines locally.
Text File Line Ending Converter

Upload or paste text and convert CRLF, CR, and LF endings to a consistent LF or CRLF output locally.
Unix Timestamp Converter

Unix timestamp ⇄ human date — seconds / milliseconds / ISO 8601 — UTC and local — browser-only
TOML Formatter + Converter

TOML formatter + converter — format/validate TOML 1.0, convert TOML ↔ JSON ↔ YAML, with error line/column.
TSV to CSV Converter

Turn tab-separated files into standards-friendly CSV with proper quoting, download, and local processing.
TSV to JSON Converter

Tab-separated data to JSON, header detection, type inference, quoted tab/newline fields, browser-only
Two's Complement Converter

Signed decimal to two's complement binary and hex at 4, 8, 16, 32, 64 bits, with sign-magnitude and one's-complement steps, runs in your browser
TypeScript Cheatsheet

TypeScript cheat sheet — 100+ snippets for types, generics, utility types, narrowing, async patterns.
TypeScript to Zod Schema

TypeScript to Zod schema converter — paste interface/type, get z.object() schema, supports unions/optionals/nested/generics/enum/Record/Map/Set.
ULID Generator

Sortable, URL-safe unique IDs — batch generate, monotonic mode, decode the timestamp back out — 100% in your browser
Unicode Character Inspector

Inspect any text character-by-character: code points, UTF-8/UTF-16 bytes, HTML entities, JS escapes, names, and hidden zero-width / confusable glyphs.
Unicode Normalizer

Normalize text to NFC, NFD, NFKC or NFKD, see code-point and byte counts shift, spot which characters changed, copy in one click, all in your browser
URL Deduplicator

Find duplicates and keep one clean copy of urls from pasted text or uploaded local files.
URL Extractor

Extract, dedupe, and export urls from pasted text or uploaded local files.
URL List Converter

Convert urls from pasted text or uploaded local files.
URL List Validator

Validate and explain issues in urls from pasted text or uploaded local files.
URL Normalizer

Normalize, sort, and prepare urls from pasted text or uploaded local files.
URL Parser

Break any URL into protocol, host, port, path, query and hash, with a decoded parameter table, all in your browser
URL Query Params Extractor

Extract, deduplicate, inspect, copy, and export query parameters from one URL or many URLs locally.
User-Agent Parser

Parse any User-Agent string into browser, engine, OS, device type and bot flag — paste a log line or read your own — browser-only
UTF-8 Byte Counter

Count UTF-8 bytes, UTF-16 code units, Unicode code points and characters in any string, right in your browser
UTM Link Builder

UTM link builder — track campaign source, medium, name. GA4/Google Analytics compatible.
UUID Deduplicator

Find duplicates and keep one clean copy of uuids from pasted text or uploaded local files.
UUID Extractor

Extract, dedupe, and export uuids from pasted text or uploaded local files.
UUID Generator

Generate v4 random, v7 time-ordered, NIL, and Short UUIDs instantly — entirely in your browser.
UUID List Converter

Convert uuids from pasted text or uploaded local files.
UUID List Validator

Validate and explain issues in uuids from pasted text or uploaded local files.
UUID Normalizer

Normalize, sort, and prepare uuids from pasted text or uploaded local files.
UUIDv7 Generator

Time-ordered, sortable UUIDs by RFC 9562: batch generate, monotonic mode, decode the embedded timestamp, all in your browser
Vim Cheatsheet

Vim cheat sheet — 100+ commands covering modes, motions, edits, search, registers, splits, with mnemonics.
Vue 3 Cheatsheet

Vue 3 cheat sheet — Composition API, reactivity, components, directives, Pinia, with side-by-side Options API comparison.
XML Formatter & Validator

Pretty-print, minify, and validate XML in your browser — preserves CDATA, comments, and namespaces.
XML to CSV Converter

Turn repeating XML records into a CSV table, columns are the union of every field, attributes optional, custom delimiter, RFC 4180 escaping, browser-only
XML ⇄ JSON Converter

XML to JSON converter — preserves attributes, nested elements, CDATA. Reversible.
XML to YAML Converter

Paste XML, get clean YAML. Attributes as @ keys, repeated tags as lists, mixed text kept, valid YAML 1.2. Browser only.
YAML Formatter & Validator

Format and beautify YAML — re-indent, validate, minify, sort keys.
YAML to CSV Converter

Turn a YAML list of objects into an RFC 4180 CSV — column union, JSON or flattened nested values, comma / semicolon / tab, browser-only
YAML ⇄ JSON Converter

Convert between YAML and JSON — both directions, pretty-printed, error messages with line numbers — browser-only
YAML to XML Converter

Turn YAML into clean, indented XML. Keys become elements, lists repeat, @keys become attributes, every value escaped. Browser-only.
ZIP Manifest Inspector

Read a ZIP central directory locally and flag traversal paths, encryption, duplicate names, and risky ratios.

AI Eval Planner

API Key Generator

ASCII Table Generator

ASCII Table Reference

awk + sed Cheatsheet

AWS CLI Cheatsheet

Barcode Generator

Number Base Converter

Base32 / Base58 Encoder & Decoder

Base62 Encoder & Decoder

Base64 Block Deduplicator

Base64 Block Extractor

Base64 Block List Converter

Base64 Block List Validator

Base64 Block Normalizer

Base64 to File Converter

Base64 to Hex Converter

Bash Cheatsheet

Basic Auth Header Generator

Batch File Rename Planner

Bcrypt Generator

Bitwise Calculator

CSS Border Radius Generator

Cache-Control Builder

Case Converter

Code Screenshot Generator

Collatz Conjecture Calculator

Color Blindness Simulator

Color Contrast Checker

Color Converter

Column Align

Common Ports Reference

CORS Header Generator

CRC32 Checksum Calculator

Credit Card Number Deduplicator

Credit Card Number Extractor

Credit Card Number List Converter

Credit Card Number List Validator

Credit Card Number Normalizer

Test Credit Card Number Generator

Cron Expression Explainer — Decode Any Cron + Next 20 Runs

Crontab Helper — Visual Builder & Explainer

CSP Generator

CSP Policy Auditor

CSS Button Generator

CSS clamp() Fluid Typography Generator

CSS Filter Generator

CSS Font Stack Generator

CSS Formatter & Minifier

CSS Grid Visual Generator

CSS Grid Generator

CSS Keyframes Animation Generator

CSS Media Query Generator

CSS Minifier

CSS Scrollbar Generator

CSS Specificity Calculator

CSS to Style Object

CSS Transform Generator

CSS Triangle Generator

CSS Variable Deduplicator

CSS Variable Extractor

CSS Variable List Converter

CSS Variable List Validator

CSS Variable Normalizer

CSV Column Extractor

CSV Data Quality Profiler

CSV Deduplicator

CSV Filter

CSV Header Normalizer

CSV Sorter

CSV Stats Summary

CSV ⇄ JSON Converter

CSV to Markdown Table

CSV to SQL Converter

CSV to TSV Converter

CSV to XML Converter

CSV to YAML Converter

CSV Transposer

Cubic Bezier Editor

curl Cheatsheet