What you do on the board
A run starts with four numbered tiles. In Classic mode, you can study their positions for as long as you want. Tapping 1 covers the remaining numbers. You then choose 2, 3 and 4 from the face-down tiles, in that order.
Clear a board and the next one has one more number. Choose a wrong tile and that board ends: the numbers are revealed, you receive a strike, and the next board keeps the same number of tiles in new positions. Three strikes finish the run. Tapping an empty square or a tile already cleared does nothing.
The board always has forty spaces. It is five columns by eight rows on a phone and transposed on a wide screen. Up to nine numbers, occupied squares do not touch, even at a corner. From ten onwards they can. A larger board therefore changes the arrangement as well as the number you are remembering.
Classic and the two timed looks are different tasks
Classic lets you decide when you have looked enough. The other modes cover the numbers automatically after 1,000 ms or 500 ms. In those modes, you wait for the cover before answering, including finding 1.
That changes the job. Classic gives you time to rehearse a route. A fixed look asks you to take in the layout within a short window. Keep the mode the same when comparing runs. A longest board of eight in Classic and eight after a half-second look are not interchangeable results.
What the longest-board score means
The headline is the largest board you cleared completely, not the number of correct taps or the number of boards you played. If you clear four, five and six, then use all three strikes on seven, your longest board is six. You cleared three boards and played six.
It is not a direct count of separate items in your memory. In Classic, you see 1 when you choose it. At the end, only one uncleared tile remains. You can also remember several positions as a single route. Those features make the score useful for this practice, but unsuitable as a general memory-capacity number.
A run that reaches its end can be saved in this browser; one you stop early is not saved. Use your same-mode history as a record of what happened. The site does not supply a research-based pass mark for this version, and a high number does not establish a photographic memory.
Where the name comes from
In Inoue and Matsuzawa's 2007 study, Working memory of numerals in chimpanzees, chimpanzees learned to select numerals in ascending order on a touchscreen. The researchers then covered numerals after the first selection, making their former positions necessary for the remaining choices.
A separate fixed-duration comparison used five numerals shown for 650, 430 or 210 ms. It compared Ayumu, his mother Ai and nine university students. Ayumu retained his accuracy as the display became shorter, while Ai and the students became less accurate. This was a particular task with particular participants, not a general ranking of the two species.
Experience also matters to the interpretation. Cook and Wilson's 2010 follow-up reported that two university students exceeded the earlier chimpanzee performance after practice. That small follow-up does not settle every question about memory across species. It does show why a familiar task and an unfamiliar one cannot simply be treated as equal starting points.
QuickenBrain uses different display times, a different board and a rising tile count. Matching a number from a video of Ayumu is not replicating that experiment.
A practical method: remember a route
Start in Classic. Find 1, then follow the route through every number before making the first tap. Notice turns and groups: across the top, back through the middle, then down to a corner. You are looking for an order you can retrace, not trying to preserve a perfect picture.
When the numbers are covered, follow that same route. After a mistake, use the reveal to find the exact link that broke. Did you exchange two neighbours, forget the turn, or choose the next tile before finishing the current one? That is a more useful observation than calling the whole run bad.
Try a fixed look when you want to change the task, not because it makes an older score count for more. Keep the same device and viewing arrangement when you want a close comparison.
Try the method here
The Trace the route lesson shows how to divide a numbered path at its turns. Then open the Chimp test practice and choose Classic or a timed look. For a task where positions arrive one after another instead of together, try Sequence memory.
Questions people ask
What is the Chimp Test?
The Chimp Test is a memory task. Numbered tiles appear on a board. You choose 1, the other numbers are covered, and you find the rest in order from memory. Each cleared board adds one number. The name comes from Inoue and Matsuzawa's 2007 study, in which chimpanzees chose numerals in order on a touchscreen, and the rest were covered after the first choice.
Did a chimpanzee really beat people at this task?
In one particular task, yes. In the 2007 study, the chimpanzee Ayumu kept his accuracy as five numerals were shown for shorter times, while his mother Ai and nine university students became less accurate. Cook and Wilson's 2010 follow-up reported that two students exceeded the chimpanzee performance after practice. Neither study ranks the two species in general.
What does a Chimp Test score mean?
On this site it is the largest board you cleared completely, in that mode. It is not a count of separate items in your memory, because in Classic you see 1 when you choose it, and you can remember several positions as one route. The site gives no research-based pass mark for this version, and a high number does not establish a photographic memory.
What is a good method for the Chimp Test?
Remember a route, not a picture. Start in Classic. Find 1, then follow the path through every number before the first tap. Notice turns and groups, such as across the top, back through the middle, then down to a corner. When the numbers are covered, follow the same route. After a mistake, use the reveal to find the link that broke.
How many mistakes can you make in the Chimp Test here?
Three. Choose a wrong tile and that board ends: the numbers are revealed, you receive a strike, and the next board keeps the same number of tiles in new positions. Three strikes finish the run. A run starts with four numbered tiles on a board of forty spaces, and each board you clear adds one number to the next.