30 Browser Tools Every Developer Should Bookmark

I have a folder in my bookmarks bar called "tools." It holds these thirty links. Most of them I use for ten seconds at a time — prettify a JSON blob, look up an HTTP status, base64 a string, eyeball a regex. CLI installs are too heavy for that. VS Code extensions are too slow to dig through. The browser tab is the right place.

The list is grouped by what I actually reach for, in the order I reach for it. Every page is fully client-side: nothing you paste leaves the tab.

1. JSON / YAML / config (5 tools)

1. JSON Formatter

The single tab I open more than any other. Backend ships me a single-line 12 KB response and this thing prettifies, folds, and lets me search by JSONPath. Five megabytes loads in well under a second. Pinned to the first slot in my taskbar, no other formatter has held that slot for as long.

2. YAML Formatter

For Kubernetes manifests and GitHub Actions workflows, indentation is the whole game. This catches the off-by-one space, flags duplicate keys, and gives you a tree view. Faster than kubectl apply and reading the error.

3. YAML to JSON

Got a docker-compose.yml that needs to feed something JSON-only? Paste, click, copy. I also use it the other way around — I think in JSON structure first, then translate to YAML for Helm values.

4. CSV to JSON

Ops drops a CSV in Slack and I need it in a database. CSV → JSON → batch insert is the path every time. Headers become keys, empty cells stay null, escaped quotes survive.

5. XML to JSON

Legacy systems still speak XML. SOAP, RSS, Android resource files. Paste in, get the tree, decide how to parse. Faster than wrestling with xml2js configuration.

2. Cheatsheets (8 tools)

6. Git Cheatsheet

The difference between git reset --hard and git reset --soft is something I look up every three months. Beats searching Stack Overflow and dodging ads. Covers rebase, cherry-pick, and the reflog rescue moves.

7. Vim Cheatsheet

Local cheat.sh is great, but when I'm SSH'd into a jumpbox and editing in vim, popping a browser tab to confirm :%s/foo/bar/gc syntax is the fastest path. Movement, editing, search — all on one page.

8. Bash Cheatsheet

${var%.*} vs ${var%%.*} — which one strips more? I verify every time. This page breaks parameter expansion, loops, and test expressions into chunks I can scan in three seconds.

9. Docker Cheatsheet

The argument order for docker run always trips me up after a few weeks away. Build, run, networking, and volume sections cover about 80% of what I touch on a normal day.

10. Kubectl Cheatsheet

When a pod is stuck, the rescue sequence is the same: get pod -o wide, describe, logs --tail=100 -f, port-forward. Print this page, tape it to your monitor.

11. SQL Cheatsheet

JOIN types fade after six months of not writing SQL. INNER / LEFT / FULL OUTER with diagrams, plus the window functions I actually use — ROW_NUMBER, RANK, LAG — saves me from writing a query I'll have to redo.

12. Regex Cheatsheet

Lookarounds: (?=), (?<=), (?!), (?<!). I remember what they do, I never remember which is which. Organized by assertion / quantifier / character class / capture group, two-second recall.

13. Tailwind Cheatsheet

space-x vs gap, arbitrary value syntax like grid-cols-[200px_1fr], every modifier prefix. Grouped by layout / spacing / typography / color / responsive. Finding a class doesn't drown you in the way the official docs sometimes do.

3. Crypto / hashing / encoding (4 tools)

14. Base64 Encoder/Decoder

HTTP basic auth test fixtures. Encoding files for data: URIs. Decoding nginx auth_basic_user_file entries. Faster than remembering the -n flag on echo -n "..." | base64.

15. JWT Decoder

A 401 in production: paste the token, look at exp, look at iss, find the bug. Fully local parsing matters here — a production token belongs in your tab, not on someone's analytics dashboard.

16. JWT Encoder

Hand-craft a JWT for tests. Pick the algorithm, fill the payload, drop in the secret. I use it constantly for e2e tests where I need tokens for different user roles.

17. MD5 / SHA Hash Calculator

File integrity checks, signature comparisons, hashing a string to use as a cache key. MD5 / SHA-1 / SHA-256 / SHA-512 all on one page, no tool-switching.

4. DevOps / ops (5 tools)

18. Cron Expression Explainer

0 */6 * * 1-5 — does that really run every 6 hours on weekdays only? Paste it, get the next five execution times. Saves you from getting paged at 3am because your "weekday only" job ran on Sunday.

19. Crontab Helper

Pick "every day at 9am" or "Mon/Wed/Fri at 2am" from dropdowns, get the cron expression. Handy when you're pairing with someone who doesn't have cron syntax in muscle memory.

20. HTTP Status Code Explorer

What is 418, when do you use 307 vs 308, what triggers 426. Search by number or by scenario. Faster than scrolling MDN.

21. DNS Record Type Explainer

SPF, DKIM, DMARC: what goes in the TXT record? CAA records to restrict cert issuance: what's the syntax? Each record type with a real example next to it.

22. Linux Permission Calculator

755 and 644 I know cold. But 1777 (sticky bit) and 4755 (setuid) come up when I'm debugging something weird. Check the boxes, get the number. Paste a number, get the boxes.

5. Text / data wrangling (4 tools)

23. Text Deduplicator

A log dump with 1000 IPs that need to be deduped. Faster than typing sort | uniq in three places, and it tells you the input count, output count, and duplicate ratio.

24. Text Sorter

Sort alphabetically, numerically, by length. Ascending, descending, reversed. I use it for import statements, SQL IN lists, environment variables — anywhere humans should look at sorted lines.

25. Text Diff

When the two strings to compare are pasted from a chat, opening a local diff tool is overkill. Line-level and character-level granularity, red/green output, done in a tab.

26. UUID Generator

Test fixtures, database primary keys, trace IDs. Generate 1 to 100 at a time, one click to copy all. v4 by default, v1 and v7 also supported.

6. Color / design (4 tools)

27. Color Picker

Sample a color, convert between HEX / RGB / HSL synchronously, copy in the format your design tokens want. For when opening Figma is too much friction.

28. Image Color Extractor

Designer drops a screenshot and says "match this palette." Upload, get 5-10 dominant colors with HEX codes, copy. Beats clicking the eyedropper around in Photoshop ten times.

29. CSS Gradient Generator

Linear gradients I can write by hand. Conic gradients I cannot. Drag stops, see the preview update, copy the CSS. Works with radial too.

30. Color Contrast Checker

WCAG AA wants 4.5:1 for body text, AAA wants 7:1. That pale gray your designer loves looks fine in Figma and fails accessibility tools in production. Catch it before merge.

How to combine them

Three combinations earn their keep on a normal day:

The integration flow: JSON Formatter + JWT Decoder + HTTP Status Explorer, all pinned. When an API call goes sideways, 30 seconds tells you whether the protocol, the token, or the data shape is the broken thing.
The DevOps flow: Cron Explainer + Crontab Helper + Linux Permission Calculator. Validate your cron and your permission bits in a browser before you ship the script. Future-you, at 3am, will thank present-you.
The design flow: Color Picker + Image Color Extractor + Contrast Checker. After building a component, screenshot it, extract the palette, run contrast against the background. PR review with the designer gets thirty seconds shorter.

Make a folder. Drop the thirty links in. The hours per year that returns will surprise you.

Made by Toolora · Updated 2026-05-26