Marathon Odd One Out

A free brain training test.

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How to play

• A grid of identical-looking colour tiles appears.
• One tile is a very slightly different shade.
• Tap that odd tile as quickly as you can spot it.
• The difference shrinks as you progress — eyes sharp!
• Trains fine colour perception and visual search.

Features

• Odd One Out cognitive test built on real psychology
• Marathon difficulty over 22 rounds
• Shareable Brain Score, letter grade and brain-age estimate
• Tracks your personal best, with mutable audio cues
• Plays on touch and desktop, reduced-motion friendly

Ready to play?

A free brain training test.