Free brain-training game
About Code Shift
Code Shift is a mental transformation game: a short code like 4 – 8 – 2 flashes up and disappears, then instructions arrive one at a time — swap the first and last digits, add two to the middle digit, remove the largest digit. You rewrite the hidden code in your head at every step and type the final result. Every four solved codes cracks open a vault for a bonus.
How to play Code Shift
- 1Memorise the code while it's on screen — it disappears after a few seconds.
- 2Apply each transformation mentally as it appears: swaps, additions, subtractions, removals, insertions and reversals.
- 3When the changes stop, type the final code on the keypad and confirm.
- 4A correct code fills a vault segment; a wrong one ends the run. Codes get longer and chains get deeper as you go.
What Code Shift trains
Code Shift trains working memory manipulation: you hold a sequence you can no longer see and actively rewrite it step after step. That's a heavier load than simple recall — each transformation forces you to refresh every digit's identity and position.
Learn about Working Memory Exercises and Games for Adults →Tips & strategy
- Rehearse the code aloud in your head after every transformation, not just at the start.
- Track positions, not just values — most errors come from applying a change to the wrong slot.
- For REVERSE, flip your mental reading direction rather than rebuilding the whole code.
Frequently asked questions
Is Code Shift free to play?
Yes — Code Shift runs free in your browser, no download required.
What transformations appear in Code Shift?
Swapping digits, adding or subtracting from a position, removing the largest digit, inserting new digits at either end, and reversing the whole code at higher levels.
How does the vault work?
Every solved code fills one of four vault segments. Completing the vault pays a 50-point bonus and starts the next one.