Free, private, no accounts — everything stays on your device.
Chrae Lab is a collection of free online tools: a retirement (FIRE) planner, a unit converter, a scientific calculator, a to-do list, Sudoku puzzles, a bingo number caller and a TV buying guide. Each one runs entirely in your browser — no sign-up, no ads, and nothing sent to a server.
Plan long horizons with numbers that stay on your device.
Everyday converters and calculators, no ads in the way.
Small tools for keeping track of things.
Quick browser games for a short break.
Four difficulties, pencil marks, hints — progress saved on your device.
Random number caller for real-life bingo — 75, 90 or 30 ball, with a flashboard and call history.
Play Go online against another person — quick match or a private room, 9×9 to 19×19, no account.
魔塔 — ten towers of 99 generated floors. Every fight is arithmetic; every floor is a puzzle.
A 3D city simulation with a progression ladder. Zone, build, tax and watch a statistical model of a city respond.
Short reads that go with the tools — no app needed.