Free browser practice

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Practice anywhere

Get Locker on your phone

Save your real combination on your device and practice with clicks and haptics.

Coming soon to the App Store Coming soon to Google Play

The mobile app

Learn each turn, then practice on your own

Locker app home screen with practice options — Your locker, ready to practice

Form for saving a locker combination privately on an iPhone — Save your combination on-device

Teach Me guide explaining the four steps for opening a combination lock — Follow four clear steps

Interactive blue combination lock dial in the Locker app — Turn a realistic dial

Locker app explaining in plain words that the lock was pulled too early — Understand every mistake

Locker app settings for dial range, size, sensitivity, sound and appearance — Match the dial to your locker

Learn before the first day

New school locker? Practice opening it before you have to do it in a crowded hallway. Locker uses the same right-left-right sequence as a physical combination lock.

Spin the dial, stop on each number and pull the shackle. If you make a mistake, Locker gives a clear explanation — such as “You went past your second number” — instead of silently resetting.

Combination lock practice that teaches

Dials numbered 0–29, 0–39 and 0–49
A Teach Me walkthrough with right and left arrows
A plain-words explanation for every mistake
A realistic dial for touchscreens, trackpads and mice
No account, ads or tracking

For school, gym and work lockers

Use the free browser version for practice locks. The mobile app will let you save your own school, gym, workplace or college dorm combination on your phone only.

Privacy, briefly

No accounts. No ads. No tracking. Your combination never leaves your device. Read the full privacy policy.

Made by Cannappy LLC. Questions? Get support.