Are You Smarter Than a Chimp?

weirdly accurate.

Are You Smarter Than a Chimp?

Are you smarter than a chimp?

On the chimp test, probably not on your first try. In a 2007 study at Kyoto University, a young chimpanzee named Ayumu got about 79% of trials fully right when five numbers flashed for 210 milliseconds, roughly a fifth of a second. Nine university students doing the same task got about 38%. With enough practice, though, people catch up with Ayumu and can even beat him.

This chimp test is the limited-hold task from Sana Inoue and Tetsuro Matsuzawa’s 2007 study, turned into a short ladder. You touch a white circle, numbers from 1 to 9 appear in random spots on a 40-position grid, and after a set time they all turn into white squares. You touch the squares smallest first; one wrong touch makes the whole trial wrong. After one untimed warm-up you climb seven steps: five numbers shown for 650, then 430, then 210 milliseconds (the study’s three speeds), then six, seven, eight and nine numbers at 210 ms. One fully right trial clears a step; a miss gets one more try at that step, and the second miss ends the run, so a run is at most eight trials. Display times are counted in your screen’s frames, and a trial is shown again if the screen drops one. Your result is the last step you cleared. To compare it with the study, Ayumu’s and the nine students’ accuracy at each speed is put through the same ladder rules: Ayumu would clear the 210 ms step in about 82% of runs, the students in about 43%.

It is not an IQ test and not a check of memory health. It measures one narrow skill: how much of a screen you can take in with a single glance and hold for a moment. A run is short, so one slip can end it early, and a phone is smaller and slower to touch than the lab’s large monitor with 3 cm numerals. There is no large population sample for this task, so your result is placed against named reference points, not a percentile, and the study never tested Ayumu with more than five numbers.

What the chimp test measures

One skill, the one Ayumu is famous for: remembering where several numbers were after a single glance.

The task

  • The limited-hold numeral task from Inoue & Matsuzawa (2007) at Kyoto University’s Primate Research Institute: five numbers from 1 to 9 in random positions on an 8 × 5 grid
  • The numbers stay up for 650, then 430, then 210 ms, and turn into white squares; touch the squares smallest first
  • One untimed warm-up, then a ladder of seven steps: the three speeds with five numbers, then six to nine numbers at 210 ms
  • One right trial clears a step; a miss gets one more try, and the second miss ends the run, so a run is at most eight trials
  • On each speed step, a line saying how often Ayumu and the students got a single trial right at that speed

Your result

  • The last step you cleared: the shortest flash you got through, and at 210 ms how many numbers you held
  • Ayumu and the nine students put through the same ladder: Ayumu would clear the 210 ms step in about 82% of runs, the untrained students in about 43%
  • Reference points for a single 210 ms trial: Ayumu about 79%, his mother Ai about 22%, nine untrained students about 38%, one standard deviation above the students’ average about 57%, two students after 15,000 practice trials 94% and 96%
  • Your accuracy by how many numbers there were, and how quickly your first touch came
  • The steps you cleared in every run on this device, so you can watch practice move the line
  • A shareable card and a link that challenges a friend to climb further

Before you start

  • About a minute
  • Works on a phone or a computer; on a phone held upright the grid stands up (5 × 8) so the squares are bigger
  • Your browser needs 3D graphics (WebGL) switched on; sound is optional, just short clicks and tones
  • Free, no sign-up

Chimp test FAQ

Is this test free? Do I need to sign up to see my result?

Yes, it’s free, and there’s nothing to sign up for: no account, no email, no payment. Your result appears on this page the moment you finish, and you can share it or play again straight away.

What is the chimp test?

The chimp test is a short-term memory task first given to chimpanzees at Kyoto University’s Primate Research Institute. Several numbers from 1 to 9 flash on a touch screen, turn into blank squares, and you touch the squares in numerical order. It became famous in 2007, when Sana Inoue and Tetsuro Matsuzawa reported that a young chimp named Ayumu beat nine university students when the numbers were shown for only 210 milliseconds. This version keeps the study’s 650, 430 and 210 ms display times.

What is a good score on the chimp test?

Clearing the 210 ms step, the third of seven, is a good result for someone who hasn’t practised. In the 2007 Kyoto study, nine untrained university students got about 38% of single trials right at 210 ms; put through this test’s ladder, that clears the 210 ms step in about 43% of runs. Ayumu the chimp got about 79% of trials right, which clears it in about 82% of runs. The steps with six to nine numbers go beyond what the study tested. Guessing five squares in the right order works only once in 120 tries.

Can a human beat Ayumu the chimp?

Yes, with practice. Alan Silberberg and David Kearns tested themselves in 2009 and both reached Ayumu’s level at 210 ms; one of them needed about 2,500 trials. In 2010 Peter Cook and Margaret Wilson trained two students for 15,000 trials at 650 ms, after which the students scored 94% and 96% at 210 ms, better than Ayumu. Ayumu had practised for a long time, while the original nine students did one session each.

Why are chimps so good at the chimp test?

Nobody knows for sure. Tetsuro Matsuzawa proposed that the common ancestor of humans and chimpanzees had this kind of instant visual memory and that humans traded some of it away as language evolved; that is a hypothesis, not a finding. Cook and Wilson (2010) saw their trained students drop to 77% and 81.5% when the white squares were replaced with a digit-like pattern, which suggests part of the skill rests on the ordinary afterimage a bright flash leaves. Ayumu was also unusual: the only one of six chimpanzees to reach that level.

Does the chimp test measure IQ?

No. The chimp test measures one narrow skill: how many positions you can take in with a single glance and keep for a moment. It is not an intelligence test, and a low score does not mean a chimpanzee is smarter than you in general. It is not a check of memory health either; anyone worried about their memory should talk to a doctor. A run has one or two trials per step, so one slip can end it early.

Why does the chimp test use 0.21 seconds?

Inoue and Matsuzawa chose 210 milliseconds because it is close to the time human eyes need to jump to a new spot, a saccade. In that time there is no chance to look around the screen: you get one glance. A cinema film shows about 5 frames in the same time. This test counts the display time in your screen’s frames, 13 frames on a 60 Hz screen, and shows a trial again if the screen drops a frame.

How long does the chimp test take, and does it work on a phone?

The chimp test takes about a minute: one warm-up trial and at most eight scored trials on a seven-step ladder. It runs in the browser on a phone or a computer, free and without sign-up, and needs 3D graphics (WebGL) switched on. On a phone held upright the grid turns to 5 × 8 so the squares are bigger. The lab used a large touch monitor with 3 cm numerals; a phone is smaller and slower to touch.

Where the numbers come from

There is no large population sample for this task: the human group in the original study was nine university students, one session each. Your result is placed against named reference points from the papers below, never a percentile. The 650 ms and 430 ms values and Ai’s values are read off Figure 2 of Inoue & Matsuzawa (2007) and may be off by about 2 points; the 57% line is read off Figure 1 of Silberberg & Kearns (2009). Ayumu’s and the students’ chances of clearing each step of the ladder are calculated from those per-trial values with this test’s rules, treating trials as independent; nobody in the studies played the ladder. For Matsuzawa (2009) only the abstract was read. The site does not publish its own players’ data.

How the chimp test is scored

Limited hold

The numbers stay on screen for a fixed time and are then covered, as in the 2007 study. Only the warm-up trial waits for your first touch before covering them.

Fully right

A trial counts only if every square is touched in the right order. One wrong touch ends the trial as wrong; touching an empty spot is not counted as an answer.

Frames, not the clock

Display times are counted in screen frames: on a 60 Hz screen 39, 26 and 13 frames, or 650, 433 and 217 ms. If a frame is dropped by more than half a frame’s length, the trial is shown again.

The ladder

One fully right trial clears a step. A miss gets one more try at the same step, and the second miss anywhere ends the run. The study’s side is worked out, not measured: Ayumu’s and the students’ share of trials right at each speed in Figure 2 of Inoue & Matsuzawa (2007), put through the same rules as if every trial were independent.