Tools for Teacher
175 hand-picked tools for Teacher. Free, private, browser-based.
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24-Point Solver & Game
24-point solver and game — enter 4 numbers and get every solution instantly, or play random hands against the clock.
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Chinese Acupoint Locator
200+ meridian acupoints / WHO 2008 standard locations / with contraindications, manipulation, and combinations.
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Age Calculator
Calculate your exact age — years, months, days, hours. Compare two dates or count to a future date.
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AI Lesson Plan Prompt Builder
Template-driven prompt generator for lesson plans, formative quizzes, and rubrics — by grade level and subject.
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Arabic 1100 Essential Words
Arabic 1100 essential A1–A2 MSA words — Arabic script with full ḥarakāt, DIN 31635 romanization, gender, three-form verbs, audio TTS.
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Arithmetic Sequence Calculator
Arithmetic sequence calculator — nth term, sum of the first n terms, and the common difference from any two terms, all in your browser.
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Atom Economy Calculator
product molar mass ÷ Σ reactant molar masses × 100 — green-chemistry atom efficiency, with how it differs from percent yield — browser-only
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Number Base Converter
Number base converter — binary, octal, decimal, hex, and any base 2-36. Bitwise too.
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Batch File Rename Planner
Upload a batch, generate safe new filenames with sequence numbers and case rules, then export a CSV plan.
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Bingo Card Generator
Classic 75-ball B-I-N-G-O, UK 90-ball tickets, or your own words — print up to 30 unique cards, crypto-random, browser-only
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Binomial Expansion Calculator
Expand (a + b)ⁿ term by term with exact BigInt coefficients, substitute numbers like (2x + 3)⁴, and pull out any single term — browser-only
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Birthday Paradox Calculator
Birthday paradox calculator — see the probability of shared birthdays in a group of N people, visualized step by step.
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Braille Translator
Type text and read it back as Unicode braille dots, or paste braille to recover the letters, all in your browser
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Buoyancy Force Calculator
F = ρ·V·g · Archimedes' principle · will it float or sink · fresh/sea water + air presets · apparent weight · 100% browser-only
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Centripetal Force Calculator
Solve F = m·v²/r for force, mass, speed or radius, with angular speed ω and centripetal acceleration, browser-only
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Chemistry Equation Balancer
Chemistry equation balancer — paste an unbalanced equation, solve coefficients using the matrix method, show step-by-step.
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Chengyu Chain Game
Chengyu chain game with a 30,000+ idiom dictionary (full 汉语成语大词典 coverage). Start with any idiom; the computer continues with one whose first character matches your last.
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Chinese Idiom Search
800+ everyday chengyu — pinyin, origin, usage.
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Chinese Name Generator
Chinese name generator — meaningful Chinese names with pinyin, meaning, and stroke count.
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Chinese Numeric Converter
Arabic ⇄ Chinese number — simple (一二三), formal (壹貳參), or amount (金额大写 with 元角分).
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Chinese Pinyin Converter
Chinese characters to pinyin — with tone marks or numbers, supports simplified and traditional.
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Chinese Poetry Search
Chinese classical poetry — 300+ hand-annotated Tang/Song/Yuan canon (唐诗宋词元曲) plus 80,000+ searchable Tang/Song/Shijing/Chuci poems on demand.
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Chinese Stroke Counter
Chinese character stroke counter — count strokes for any hanzi, traditional or simplified.
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Chinese Zodiac Sign Checker (Sheng Xiao)
Chinese zodiac checker — your animal sign, element, compatibility, lucky numbers/colors by birth year.
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Circle Calculator
Know any one of radius, diameter, circumference or area, get the other three, plus arc length and sector area, browser-only
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Circle of Fifths
Interactive circle of fifths, click any major key for its key signature, relative minor, scale and dominant
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Classroom Color Wheel
Interactive color wheel with harmony explorer and color mixing — complementary, analogous, triadic, split-complementary, and tetradic schemes for teachers and students.
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College Major Matcher (Holland RIASEC, 40 Questions)
College major matcher — Holland code (RIASEC) test, 40 questions, recommend 10+ matching majors with career path.
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Combined Gas Law Calculator
P1V1/T1 = P2V2/T2 solver, find any one of the six gas quantities, with Boyle, Charles and Gay-Lussac special cases, browser-only
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Completing the Square Calculator
Turn ax² + bx + c into vertex form a(x − h)² + k with every step shown — vertex, axis of symmetry, min/max, and solved by completing the square — browser-only
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Complex Number Calculator
Complex number calculator — +-×÷ + conjugate + modulus + argument + polar/Cartesian conversion + powers + roots + Euler form, complex plane visualization.
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Cone Calculator
Radius + height of a right circular cone, instant volume ⅓πr²h, slant height, lateral and total surface area, plus reverse-solve, browser-only
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Coulomb's Law Calculator
F = k·q1·q2 / r² — solve electrostatic force, distance or charge, signed result, µC/nC units, scientific notation — browser-only
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Countdown Timer
Countdown timer — to any date and event, with live ticking down to seconds.
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Cylinder Calculator
Volume, surface area and capacity of a cylinder from radius or diameter and height — reverse-solve for height, see litres of water — browser-only
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Day of the Week Calculator
Type any date and read the weekday back — works for 1066, 1900 or 3000, with day-of-year, ISO week and days-from-today
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Decimal to Fraction Converter
Turn 0.75 into 3/4, type 0.(3) to get 1/3, or flip a fraction back to its decimal with the repeating block marked
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Density Calculator
Solve ρ = m / V for density, mass, or volume · mixed units (g, kg, lb, mL, L, cm³, gallon) · 20 substance presets · floats-or-sinks verdict — all browser-only
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Derangement Calculator
Subfactorial !n — the number of permutations where nothing stays in its own place, exact via BigInt, with the 1/e probability — browser-only
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Derivative Calculator (Step-by-Step)
Derivative calculator with step-by-step — symbolic differentiation, chain/product/quotient rule shown, plot f(x) and f'(x).
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Divisors Calculator
List every factor of a number — divisor count, sum of divisors, factor pairs, prime and perfect-number check — runs in your browser
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DOI Deduplicator
Find duplicates and keep one clean copy of dois from pasted text or uploaded local files.
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DOI Extractor
Extract, dedupe, and export dois from pasted text or uploaded local files.
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DOI List Converter
Convert dois from pasted text or uploaded local files.
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DOI List Validator
Validate and explain issues in dois from pasted text or uploaded local files.
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DOI Normalizer
Normalize, sort, and prepare dois from pasted text or uploaded local files.
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Double Factorial Calculator
Exact n!! computed on BigInt — the full expansion (7!! = 7×5×3×1 = 105), odd or even chain, and the bridge to the ordinary factorial, all in your browser
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Dutch 500 Essential Words
Dutch 500 essential A1–A2 words — IPA + de/het articles + 6-person conjugation + audio TTS.
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Egyptian Fraction Calculator
Turn any proper fraction into a sum of distinct unit fractions with the Fibonacci-Sylvester greedy algorithm, with the steps shown, browser-only
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English Collocations
English collocations reference — 200+ common verb + noun / adj + noun / verb + prep collocations with usage examples.
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English Grammar Rules Reference
English grammar rules reference — 60+ core grammar rules with side-by-side examples, common mistakes, bilingual explanations.
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English Irregular Verbs Reference
English irregular verbs reference — 200+ verbs with base / past / past participle, Chinese gloss, in-browser audio, pattern filter, and a flash-card practice mode.
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English Vocabulary Test
English vocabulary test — estimate your vocab size in 5 minutes, levels CET-4 / CET-6 / IELTS / TOEFL / GRE.
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Escape Velocity Calculator
v = √(2GM/r) — escape + orbital velocity for any planet, moon or star, in m/s, km/s and mph — browser-only
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Final Grade Calculator
Current grade + final weight + target → exactly what you need on the final — browser-only
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Fraction Calculator
Add, subtract, multiply, divide fractions — auto-reduced, with steps, mixed ⇄ improper ⇄ decimal — browser-only
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Free Fall Calculator
h = ½gt² · v = √(2gh) · solve from height, time, or impact speed · Earth, Moon, Mars gravity · browser-only
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French 1086 Essential Words — DELF A1, A2, B1, B2 & Professions
1086 French entries — 1036 DELF A1-B2 core words plus 50 profession words. IPA, gender, Bescherelle conjugation (présent / passé composé / futur simple), free TTS, 17 categories.
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GCD & LCM Calculator
GCD + LCM of any list of integers — Euclidean steps, prime factorization, prime-factor table — exact BigInt math, browser-only
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Geometric Sequence Calculator
Geometric sequence calculator — nth term, sum of first n terms, and infinite series sum from first term a and common ratio r, all in your browser.
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German 500 Essential Words
German 500 essential words (A1-A2 + B1 core) with IPA, der/die/das, full Präsens, Präteritum, Perfekt, Partizip II for verbs, and browser TTS.
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Go (Golang) Cheatsheet
Go (Golang) cheat sheet — 100+ idiomatic snippets covering syntax, goroutines, channels, generics, errors, stdlib.
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GPA Calculator
Weighted GPA from courses + credits + grades — US 4.0 / 4.3 and China 4.0 / 4.5 conversion, letter ⇄ percentage ⇄ point — browser-only
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Grade Calculator
Weighted course grade + what you need on the final — multi-row categories, letter grade, shareable link — browser-only
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Gravitational Force Calculator
F = G·m1·m2 / r² · solve for force, distance or mass · scientific notation · Earth/Moon/Sun presets · 100% browser-only
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Haiku Checker
Paste three lines, see 5-7-5 syllable counts per line, with off-pattern lines flagged — English heuristic, browser-only
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Half-Life Calculator
Solve any radioactive-decay unknown — initial amount, remaining amount, elapsed time, or half-life — with exact exponential math, all in your browser
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Handwriting Practice Sheet
Handwriting practice sheet generator — Chinese 米字格 / 田字格 / 四线三格 (English) PDF-ready printable.
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Henderson-Hasselbalch Calculator
Buffer pH = pKa + log([A⁻]/[HA]) — forward and reverse, acetate/phosphate/Tris/bicarbonate presets — browser-only
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Hindi 1300 Essential Words
Hindi 1300 essential A1–A2 words — Devanagari, IAST, IPA, gender, -nā verbs, audio TTS.
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Hooke's Law Calculator
F = k·x spring calculator: solve any one of force, spring constant or displacement from the other two, plus elastic potential energy ½kx² — browser-only
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HSK Chinese Vocabulary Test
HSK Chinese vocabulary test — estimate your Mandarin level (HSK 1-6) in 5 minutes with real exam words.
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Ideal Gas Law Calculator
Solve PV = nRT for pressure, volume, amount, or temperature — pick any unknown, mix any units, runs in your browser
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IELTS Band Calculator
IELTS band calculator — convert listening/reading raw scores to band, average four skills, see your overall band.
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Indonesian 500 Essential Words
Indonesian 500 essential A1–A2 words — KBBI spelling + Jakarta IPA + audio TTS. No tones, no conjugation.
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Integral Calculator (Step-by-Step)
Indefinite integral calculator step-by-step — symbolic integration, substitution + integration by parts shown, plot f(x) and F(x).
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Italian 500 Essential Words
Italian 500 essential words (A1-A2 Plida) with IPA, gender, full verb conjugation, audio TTS.
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Japanese 500 Essential Words (JLPT N5 + N4)
Japanese 500 essential words covering JLPT N5 and N4, with kana, romaji, kanji and audio TTS.
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JSONPath / JMESPath Query Tester
JSONPath / JMESPath query tester — paste JSON, write a path, see matched values + matched paths highlighted live.
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Kanji & Chinese Character Stroke Order Viewer
Kanji + Chinese character stroke order viewer — animated SVG showing correct stroke sequence + direction, with romaji/pinyin/meaning, 500+ common characters.
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Kids Allowance Calculator
Kids allowance calculator — age-appropriate weekly/monthly amount with chore-based breakdown, savings goal sandbox.
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Kinetic Energy Calculator
KE = ½mv², solve for energy, mass or speed, with formula steps and momentum, all in your browser
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Korean 500 Essential Words (TOPIK I–II)
Korean 500 essential words spanning TOPIK I and TOPIK II — start speaking Korean today with Hangul, romanization, audio TTS, and full verb conjugations.
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LaTeX Equation Editor (Live Preview)
LaTeX equation editor live — type/paste LaTeX, see math rendered live via MathJax 3 (CDN), copy as SVG/PNG/Markdown/MathML, 30+ symbol palette.
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Leap Year Checker
Is it a leap year? Type any year for a yes/no, the 4/100/400 rule worked out, Feb length, and the next leap year, browser-only
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Lens Equation Calculator
Solve 1/f = 1/do + 1/di — enter any two of focal length, object and image distance, get the third plus magnification and a real/virtual verdict, browser-only
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Light Year Converter
Type one distance, read it as light-years, parsecs, AU, light-seconds, km and miles at once, all in your browser
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Lunar Calendar Converter (Chinese Nongli)
Gregorian ⇄ Chinese Lunar (Nongli) calendar — bi-directional, accurate 1900-2100.
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Markdown Cheat Sheet
Markdown syntax cheat sheet — every rule with live preview side by side, GFM + flavors.
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Markdown Link Extractor
Upload Markdown and extract inline links, reference links, images, and bare URLs into a local CSV.
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Math Formula Reference
Math formula reference — algebra, geometry, trigonometry, calculus, statistics, all in one place.
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Matrix Calculator
Matrix calculator — add/sub/multiply/inverse/determinant/transpose/rank/RREF/eigenvalues for n×m matrices, step-by-step.
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Maze Generator
Random printable mazes as crisp SVG, pick the size, flip on the solution, download or copy in one click, all in your browser
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Molality Calculator
Molal concentration b = n / m — moles of solute per kilogram of solvent, solve any one of moles, solvent mass, or molality, or start from grams + molar mass, browser-only
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Molar Mass Calculator
Type any chemical formula — get molar mass, a per-element mass-percent table, and mass↔mole conversion. IUPAC weights, browser-only.
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Molarity Calculator
Molar concentration c = n / V — solve any one of moles, volume, concentration, or go straight from grams + molar mass — browser-only
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Moment of Inertia Calculator
Pick a shape, enter mass and size, read I in kg·m² — cylinder, sphere, rod, point mass, plus rotational KE — browser-only
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Momentum & Impulse Calculator
p = m·v and J = F·Δt = Δp — solve any one of momentum, mass, velocity, impulse, force or time, with kg·m/s, g, m/s and km/h units — browser-only
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Morse Code Translator
Text to Morse code and back — encode, decode, audio playback, ITU standard.
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Multinomial Coefficient Calculator
n! / (k1!·k2!·…) computed exactly with BigInt — ways to split n items into fixed-size groups, the multinomial-theorem term coefficient, browser-only
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Multiplication Table Generator
Single times table, full N×N grid, or the Chinese 99 chant — copy, print, share
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Music Interval Calculator
Two notes in, the interval out: name, semitones, frequency ratio and cents, plus a reverse build from root plus interval
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Chord & Note Transposer
Move a whole progression up or down by semitones or to any key, suffix and slash bass kept, sharp or flat your call
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Nashville Number System Converter
Chords to numbers and back in any key — 1 4 5 6m, slash bass, 7/maj7 suffixes kept, one-click copy — browser-only
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Next.js Cheatsheet
Next.js 15 cheat sheet — App Router, Server Components, Server Actions, dynamic routes, with examples and pitfalls.
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Office Document Inspector
Inspect DOCX, XLSX, and PPTX package structure for macros, media, embedded objects, custom XML, and size hotspots.
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Orbital Period Calculator
T = 2π·√(a³ / GM) · Kepler's third law · solve period or semi-major axis · orbital speed · Sun/Earth/Jupiter presets · 100% browser-only
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Pascal's Triangle Generator
Generate any number of rows, read off every binomial coefficient C(n,k), highlight one row as a binomial expansion, copy or share — runs fully in your browser
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PDF Page Size Inspector
Inspect PDF MediaBox and CropBox dimensions to catch mixed page sizes before print, merge, or upload.
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Pendulum Period Calculator
T = 2π√(L/g) — solve a simple pendulum's period, frequency or length, with Earth, Moon and Mars gravity, browser-only
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Percent Composition Calculator
Mass percent of every element in a compound — type a formula, read the breakdown — IUPAC atomic weights, browser-only
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Percent Error Calculator
Compare a measured value against the true value — get percent error, absolute error, relative error, and signed high/low. Plus a percent-difference mode for two trials with no accepted answer.
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Percent to Fraction Converter
Percent ⇄ fraction, both ways. 25% becomes 1/4, 3/4 becomes 75%, decimal percents and values over 100% included, fully reduced, browser-only.
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Percent Yield Calculator
actual ÷ theoretical × 100 — solve for percent, actual or theoretical yield, grams or moles, with a plain-English read on why it is below or above 100% — browser-only
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Periodic Table
Interactive periodic table — 118 elements, properties, electron config, search.
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pH Calculator
pH, pOH, [H+] and [OH-] from any one value, with an acid/base verdict and a 0-14 colour scale, all in your browser
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Photon Energy Calculator
Wavelength or frequency in, photon energy out in joules and eV — Planck equation E = hf = hc/λ, with EM band — browser-only
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Pig Latin Translator
English to Pig Latin and back, in your browser. pig becomes igpay, egg becomes eggway, with case and punctuation kept.
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Portuguese 500 Essential Words
Portuguese 500 essential words — A1 to A2 Brazilian Portuguese, with IPA, gender, conjugation, audio TTS.
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Probability Distribution Visualizer
Probability distribution visualizer — normal/t/chi-sq/F/binomial/poisson/exp/uniform PDF+CDF, P(a≤X≤b) area, z/p table replacement.
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Projectile Motion Calculator
Solve flight time, max height, range & impact speed from launch speed, angle and height — with a live trajectory plot, browser-only
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Prompt Template Library
200+ prompt templates for ChatGPT, Claude, Gemini — copy-paste, browse by use case.
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Punnett Square Calculator
Cross two genotypes — Aa × Aa or AaBb × AaBb — get the grid, the genotype ratio and the phenotype ratio, one-click copy, browser-only
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Pythagorean Theorem Calculator
Solve a²+b²=c² — find the hypotenuse, find a missing leg, or measure the distance between two points (2D & 3D). Browser-only.
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Python Cheatsheet
Python cheat sheet — 100+ idiomatic Python snippets for string, list, dict, file, async, with real examples.
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Quadratic Equation Solver
Quadratic equation solver — ax² + bx + c = 0, discriminant analysis, real + complex roots, vertex/intercepts, parabola visualization.
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React Hooks Cheatsheet
React hooks cheat sheet — all 17 built-in hooks (useState / useEffect / useMemo / useTransition / useFormStatus...) with real examples and pitfalls.
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Readability Score Checker
Paste English text and get Flesch Reading Ease plus five grade-level scores, syllable counts, and reading time — runs entirely in your browser
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Regex Cheatsheet
Interactive regex cheat sheet — quick reference for every flavor (JS, Python, PCRE).
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Regex Visualizer
Regex visualizer — see your pattern as a railroad diagram + matching state machine, with capture groups highlighted.
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Regular Polygon Calculator
Sides n + side length s, get area, interior angle, apothem and both radii, with a to-scale n-gon drawn live, browser-only
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Roman Numeral Converter
Arabic ⇄ Roman, both directions, live — strict validation, step-by-step breakdown, vinculum up to 3,999,999 — 100% browser-only
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Russian 500 Essential Words (TORFL A1-A2)
Russian 500 essential words covering the full TORFL A1-A2 syllabus, with Cyrillic, stress marks, BGN/PCGN romanization, gender, full verb conjugation, and audio TTS.
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Rust Cheatsheet
Rust cheat sheet — 100+ snippets covering ownership, borrowing, lifetimes, traits, async, error handling.
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Schwarzschild Radius Calculator
R_s = 2GM/c² — turn any mass into its black-hole event horizon, in metres, km or light-seconds, with presets and inverse solve — browser-only
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Scientific Calculator
Scientific calculator — sin / cos / log / sqrt / power, with full keyboard input + history, deg/rad mode.
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Screen Time Budget
Screen time budget — track and visualize daily screen time across phone/tablet/PC, with age-based recommendations from WHO/AAP.
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Semaphore Flag Translator
Text to flag semaphore and back, two flag angles per letter with a drawn signaller, numeric sign for digits, runs only in your browser
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Significant Figures Calculator
Count sig figs · round to N significant figures · do sig-fig arithmetic — exact string-level math, browser-only
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Simplify Fraction Calculator
Reduce any fraction to lowest terms, see the GCD it divided by, and flip between improper and mixed forms, all in your browser
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Snell's Law Calculator
n1·sin(θ1) = n2·sin(θ2) — solve refraction angle, critical angle and total internal reflection — browser-only
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Spanish 500 Essential Words
Spanish 500 essential A1–A2 words — start speaking Spanish today, with pronunciation, example sentences, verb conjugations and audio TTS.
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Special Number Checker
Type one integer, see at a glance whether it is prime, perfect, abundant, deficient, triangular, square, cube, Fibonacci, palindrome, with the reason for each, browser-only
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Specific Heat Calculator
Q = m·c·ΔT — solve for any of heat, mass, specific heat or temperature change, with water/aluminum/iron/copper presets and J/kJ/cal units — browser-only
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Sphere Calculator
Type any one of radius, diameter, volume or surface area — the other three solve instantly, plus how many liters the ball holds — browser-only
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SQL Cheatsheet
SQL cheat sheet — 100+ statements covering SELECT, JOIN, window functions, indexing, MySQL/PostgreSQL/SQLite differences.
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Statistics Basic Calculator
Basic statistics calculator — mean/median/mode/variance/std-dev/quartiles/range/IQR/skewness/kurtosis + histogram + box plot, paste any numbers.
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Stefan-Boltzmann Law Calculator
P = εσAT⁴ — radiated power, radiant exitance and the inverse (power → temperature), with Sun and body presets — browser-only
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Sudoku Generator
Sudoku generator and solver — 4 difficulties (easy / medium / hard / expert), unique-solution guaranteed, play in the browser or print as PDF.
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Svelte Cheatsheet
Svelte 5 cheat sheet — runes ($state, $derived, $effect), snippets, props, stores, with Svelte 4 comparison.
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Syllable Counter
Count syllables in any English word or text, with a 5-7-5 haiku mode for poems
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Tally Marks Converter
Number to tally marks and back, in Unicode, the five-bar gate, or Chinese 正, with one-click copy, all in your browser
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Team Generator
Paste a name list, get fair random teams in one click, by team count or by people per team, browser-only
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Test Grade Calculator
Answers wrong → percent + letter grade + a full printable grading chart — the teacher's EZ Grader, browser-only
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Text File Cleaner
Upload a text file and remove BOM, null bytes, trailing spaces, and excessive final blank lines locally.
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Text File Line Ending Converter
Upload or paste text and convert CRLF, CR, and LF endings to a consistent LF or CRLF output locally.
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Text to Binary Converter
Text to binary (and back) — UTF-8 aware, 8/16/32 bit grouping, emoji safe.
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Thai 500 Essential Words
Thai 500 essential A1–A2 words — Thai script + RTGS + IPA + 5 tones + audio TTS.
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Traditional ⇄ Simplified Chinese Converter
Traditional ⇄ Simplified Chinese — fast, character-level, no API.
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Triangle Calculator
Triangle solver — SSS, SAS, ASA, AAS, and the ambiguous SSA case via law of sines + law of cosines. All sides, angles, area, perimeter, type, drawn to scale.
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Trigonometry Calculator
Trigonometry calculator — sin/cos/tan + inverse + sec/csc/cot, degree/radian/gradient, unit circle visualization, exact values.
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Turkish 500 Essential Words
Turkish 500 essential A1–A2 words — Istanbul standard + IPA + vowel harmony + audio TTS.
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TypeScript Cheatsheet
TypeScript cheat sheet — 100+ snippets for types, generics, utility types, narrowing, async patterns.
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Typing Speed Test
Typing speed test — WPM, accuracy, real-time mistakes, English + Chinese pinyin modes.
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Unicode Inspector and Normalizer
Inspect code points, names, categories, UTF-8 bytes and normalize text to NFC, NFD, NFKC or NFKD entirely in your browser.
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Vietnamese 500 Essential Words
Vietnamese 500 essential A1–A2 words — chữ Quốc ngữ + IPA + 6 tones + audio TTS.
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Vue 3 Cheatsheet
Vue 3 cheat sheet — Composition API, reactivity, components, directives, Pinia, with side-by-side Options API comparison.
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Wavelength Frequency Calculator
Convert between wavelength λ, frequency f, and photon energy E · c = λf · E = hf · spectrum band + visible colour · browser-only
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Weighted Grade Calculator
Items + weights → your current course grade, with letter and banked points — browser-only
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Word Counter
Count words, characters, sentences, paragraphs and reading time in any text — instant, browser-only
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Word Scrambler
Jumble the letters in any word, check if two words are anagrams, or list every ordering of a short word, all in your browser
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Work and Power Calculator
W = F·d·cosθ and P = W/t — solve work, power or force, with angle, P = F·v and HP ⇄ W — browser-only
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Wuxing Name Recommender (Five Elements Naming)
Five Elements (Wuxing) name recommender — based on Bazi gaps, suggest characters that balance the missing elements.
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Z-Score Calculator
Standardize any value, reverse a z-score back to raw, or compute μ and σ from a dataset — with left/right/two-tailed normal probabilities and percentile
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Zhuyin (Bopomofo) Converter
Hanyu Pinyin to Zhuyin ㄅㄆㄇㄈ both ways, tone marks ˊˇˋ˙, batch by space, copy in one click, runs in your browser