About KeySlice
KeySlice is a free touch-typing trainer. It runs a lesson path from the home row out to capitals, and every drill it gives you is built from two things: the keys your lesson has unlocked so far, and the keys you personally keep getting wrong. There is also an arcade run, where your typing speed is your travel speed and every word you clear is cut in half. No account needed to play, no app, no paywall — it loads fast and runs in your browser.
How it works
Every keystroke is recorded as two numbers: whether it was correct, and how long it took after the previous key. Those roll up into a per-key score kept as an exponential moving average, so recent typing counts for more than typing from a week ago. When a drill is generated, candidate words are weighted toward the keys that score worst — so a key you have mastered quietly stops consuming your practice time, and a key you are hesitating on shows up more often.
The lesson order is not invented. It follows the progression used by KTouch and GNU Typist,
which introduces two keys at a time as reaches from a home finger, starting with
J and F. A lesson only ever emits drills that are spellable from
the keys unlocked so far, which is what makes it a curriculum rather than a word list.
Practice mode adapts to you. The test is deliberately the opposite: fixed words, fixed length, fixed order, identical every session for a given lesson. Without that split, a personal best would be comparing two different tests and would mean nothing.
Why we built it
Typing tools split into two camps. Measurement tools tell you your speed but teach nothing. Courses teach a fixed sequence but ignore the fact that your weak keys are not the same as anyone else's. KeySlice is the combination: the lesson decides which keys you are allowed to meet, and your own error data decides which of them you practise.
A note on the numbers
Words per minute is a convention, not a measurement of words: it counts every five typed characters as one word, which is the standard used across typing tests so results are comparable. Accuracy and per-key timing are measured from your actual keystrokes in the browser, so background tab throttling or a dropped frame can shift a per-key latency by a few milliseconds. Your practice speed will read higher than your test speed — practice drills adapt toward your weak keys and are not a fixed benchmark. See our Terms & Conditions for the full disclaimer.
Your progress stays yours
Per-key scores live in your browser's local storage, and clearing your site data clears your progress with them. They leave your device only if you choose to sign in, which syncs them so the same record follows you to a second machine. See the Privacy Policy for what is and is not collected.
Get in touch
Found a bug or have an idea for a feature? Email hello@keyslice.app — we read everything.