Your PIN is Scrambled
“Your KeepKey shows a randomized number grid. Match positions on screen to numbers on device. The layout changes every time so screen-watchers can’t steal your PIN.”
— card 1 of 3, shown before setup
What this screen is telling you
Your PIN is never typed into your computer. The digits only ever exist on the KeepKey’s own screen. The desktop application shows a blank 3×3 grid and records which positions you click — it never learns which numbers those positions stood for.
How it works, concretely
The device screen shows something like:
7 4 1
8 2 6
3 9 5Your computer screen shows nine blank buttons in the same 3×3 arrangement. To enter the PIN 1234:
- Find
1on the device — top-right. Click top-right on the computer. - Find
2— center. Click center. - Find
3— bottom-left. Click bottom-left. - Find
4— top-middle. Click top-middle.
The next time you unlock, the device reshuffles. The same four clicks would spell a completely different number.
What attack this defeats
| Attack | What the attacker gets |
|---|---|
| Shoulder surfing | A sequence of grid positions, valid for one session only |
| Screen recording / screenshot malware | The same — positions with no digits attached |
| Keylogger | Mouse coordinates, not digits |
| Compromised desktop app | Positions. The mapping lives on the device, which the host never reads |
This is the reason KeepKey doesn’t ask you to type your PIN into a text box. A PIN typed into a computer is a PIN the computer knows.
Choosing a PIN
- 4 to 9 digits. Longer is stronger — but only if you remember it exactly.
- Not
1234, not your birth year. Grid scrambling protects the entry, not a guessable PIN. - Write it somewhere separate from your recovery phrase, or memorize it. They should never sit on the same piece of paper.
If you forget it
The device wipes itself after too many wrong attempts. That is the intended behavior — it’s what makes a stolen KeepKey worthless. A wipe is only recoverable from your recovery phrase, which is why the next card in the wizard is about writing those words down.
You can also wipe deliberately from the unlock screen via Forgot your PIN?
Related
- PIN — changing, removing, and daily use
- Your Words = Your Wallet — the next card
- All setup screens