Tools that just work.
Thirty-one small, focused web tools — open source under MIT, install as PWAs, no login required. Fork them, translate them, contribute on GitHub.
Music
Fretboard Note Trainer
Memorize every note on the guitar neck. 22 frets, 6 strings, two practice modes.
Try it →Online Metronome
Digital metronome with tap tempo, 4 time signatures, 3 sounds. Web Audio precision.
Try it →Guitar Tuner
Strobe-pattern tuner with autocorrelation pitch detection. Standard guitar plus reference tones when mic is off.
Try it →Guitar Chord Finder
Every chord, every position, with audio preview.
Try it →Guitar Scale Finder
12 roots × 9 scale types across the fretboard with audio.
Try it →Productivity
Pomodoro Timer
Beautiful focus timer with task tracking. 10 languages, offline-ready. Open source on GitHub.
Try it →Timer & Stopwatch
Beautiful countdown timer, stopwatch and date countdown. Wake Lock, background-accurate, 7-segment LED. Works offline.
Try it →Spin the Wheel
Random name picker for classrooms, raffles, decisions. Weighted entries, fairness stats, shareable URLs.
Try it →Random
Coin Flip
Flip a coin online with realistic 3D animation. True randomness, fair results every time.
Try it →Random Number Generator
Generate random numbers between any range. Cryptographic randomness — no pseudo-random shortcuts.
Try it →Dice Roller
Roll dice online — d4, d6, d8, d10, d12, d20. Realistic animation, fair RNG. D&D and board game ready.
Try it →Utilities
QR Code Generator
Generate URL, text and WiFi QR codes — 100% local, your password never leaves the browser. PNG download.
Try it →Password Generator
Cryptographically strong passwords — your device, zero upload.
Try it →Entertainment
寫真 · Celebrity Gallery
Browse celebrity photos by region. China, Korea, Japan, Taiwan, USA. Curated photo gallery.
Try it →Education
Periodic Table
Interactive table of elements — search, explore, learn.
Try it →Health
Breathing Coach
Guided breathing with animated visuals and calming audio cues.
Try it →BMI Calculator
Metric/US units. Color guide. Works offline.
Try it →Creative
Color Palette Studio
Generate harmonies, extract colors from images, export CSS.
Try it →Image Resizer
Resize, compress, convert — Canvas API, no upload.
Try it →Math
Percentage Calculator
6 modes — percent of, increase, discount, tip. Free, instant.
Try it →Unit Converter
8 categories — length, weight, temp, volume. Instant.
Try it →Text
Word Counter
Words, characters, sentences, reading time. 100% local, no upload.
Try it →Time
Age Calculator
Exact age + zodiac sign + birthday countdown.
Try it →Date Calculator
Days between dates, business days, add/subtract days.
Try it →Time Zone Converter
Convert times, plan meetings, visual overlap grid.
Try it →Finance
Tip Calculator
Split bills, calculate tips, per-country guidance.
Try it →Currency Converter
30+ currencies, static rates, free and offline.
Try it →Mortgage Calculator
Monthly payments, total interest, amortization schedule.
Try it →Developer
Hash Generator
MD5, SHA-1, SHA-256, SHA-512 — all local, instant.
Try it →JSON Formatter
Format, validate, minify — syntax highlighting, 100% client-side.
Try it →UUID Generator
Random UUIDs (v4), bulk generation, format toggles.
Try it →Why open source?
Each tool here is a single static page — no frameworks, no backend, no login required. They install as PWAs and work offline. Each is designed to do one thing well.
Everything is open source under MIT on GitHub. Pull requests are welcome — fix a bug, add a translation, propose a new tool.