Chimp Test — a free working-memory test in your browser

This is the memory task that made a chimpanzee famous. Numbers are scattered across a grid. The moment you tap 1, every other number hides behind a blank tile — and you have to keep tapping 2, 3, 4… in order, from memory alone. Clear the board and the next one has one more number.

It sounds easy at four numbers. It stops being easy somewhere around eight, because you are not remembering digits — you are remembering positions, and there is no inner voice that can rehearse a position. Free, no download, works on any phone or desktop, and your best is saved so you always have a number to beat.

How to play

• Look at the whole grid first. Nothing is timed until you commit.
• Tap 1 to start the board — every remaining number instantly hides.
• Tap the rest in ascending order from memory. Clear it and you get one more number next board.
• A wrong tap costs a strike. Three strikes and the run ends.
• Your score is the largest board you actually cleared — failing your first board scores 0.

The chimp who beat the humans

In 2007, Sana Inoue and Tetsuro Matsuzawa at Kyoto University's Primate Research Institute published a short paper in Current Biology on a young chimpanzee named Ayumu. Numerals flashed on a touchscreen for a fraction of a second, then turned into white squares; the task was to touch them in order. At the shortest display times, Ayumu was markedly more accurate than the human university students tested alongside him.

The headline — "chimps beat humans at memory" — is not the whole story. A 2009 follow-up by Silberberg and Kearns argued that the humans were effectively untrained, and that people given comparable practice closed much of the gap. The honest reading is narrower and more interesting: for very brief, spatially scattered displays, a young chimp is at least competitive with an untrained adult human, and possibly better.

One difference worth naming: this version shows the numbers until you tap 1, so it is testing your encoding strategy more than raw exposure speed. That's why the best tactic isn't reading — it's treating the layout as a shape. Chunk it: "three down the left edge, then two in the corner." Three positions become one memory, and the ceiling moves.

More games

Same wiring, different muscle: Visual Memory, Verbal Memory, Sequence Memory, or Number Memory. Or browse all games.