How Many Can You Track at Once?

weirdly accurate.

    How Many Can You Track at Once?

    How many objects can you track at once?

    Most adults can track three or four moving objects at once. The limit moves with speed: people can follow up to eight objects when they drift slowly and only one when they move very fast (Alvarez & Franconeri, 2007). In this test’s terms, the 636 adults of a 2021 study by Treviño and colleagues, replayed through its ladder from their own trials, cleared a median of two steps, that is, four balls at medium speed; 66% stopped on step 2 or 3, and a third cleared all three of the study’s steps, five balls.

    This multiple object tracking test uses that study’s task. Identical balls sit in a tray; a few light up, go plain again, and everything rolls for five seconds. When the balls stop, you tap the ones you were following. After one warm-up trial comes a ladder of five steps, one more ball each: 3 targets among 10 balls at slow speed, then 4 and 5 at medium speed. One trial with every target found clears a step and moves you straight up. A miss gets one more try at the same step; the second miss, wherever it falls, ends the run. A run is six trials at most and takes about a minute. Clear step 3 and two bonus steps follow, 6 targets among 12 balls and 7 among 14; they go past what the study measured and aren’t ranked.

    It is not a test for attention disorders, not an eyesight test and not an IQ test. The study’s people played fixed paths, while you play new random ones on a different tray and screen, so the ranking is close rather than exact, and a tired evening, a small screen or one unlucky crossing can move the result. A few runs tell you more than one.

    What the test measures

    One thing: how many moving objects your attention can follow at the same time.

    The task

    • Multiple object tracking (MOT): identical balls, a few lit up briefly as targets, five seconds of motion, then tap the targets
    • Steps 1–3 reuse trials from the TestMyBrain tracking test that Treviño et al. (2021) gave 636 adults: 10 balls, 3, 4 or 5 targets, speed steps 1 to 6
    • The ladder, one more ball each step: 3 targets slow; 4 targets medium; 5 targets medium; then bonus steps of 6 among 12 balls and 7 among 14, also medium
    • One trial with every target found clears a step; a miss gets one more try at that step; the second miss ends the run. A warm-up trial (2 targets, slow) comes first and doesn’t count

    Your result

    • How many balls you held: the targets on the highest step you cleared, and that step’s speed
    • How many of the five steps you cleared, and the share of the 636 adults, replayed through the same ladder, who got less far
    • Reference points from the same data: everyone’s average (about 2 steps), the best 5% (all 3 study steps), each age band, and phone versus computer
    • Every step’s tries, and how many of your wrong taps were balls that had passed closest to a target
    • Your number in everyday terms (children on a playground, players on a football side), a shareable card and a link that challenges a friend to climb higher

    Before you start

    • About a minute; six trials at most
    • Works with touch or a mouse; in the study’s data, 28% of people on phones and 36% of people on computers cleared all three study steps
    • Needs a browser with 3D (WebGL) switched on; sound is optional
    • Free, with no sign-up

    Multiple object tracking 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.

    How many moving objects can a person track at once?

    Usually three or four. Alvarez and Franconeri (2007) found people could follow up to eight slow objects but only one very fast one, so speed changes the answer. In this test’s terms, the 636 adults of Treviño et al. (2021), replayed through its ladder, cleared a median of two steps (four balls at medium speed); about one in three cleared all three study steps, five balls at medium speed.

    What is a multiple object tracking test?

    A multiple object tracking (MOT) test shows several identical objects, marks a few as targets for a moment, then moves them all around. When the motion stops, you pick out the targets. Researchers use it to measure how many things attention can follow at once; Treviño et al. (2021) used the TestMyBrain version, whose trials this test’s ladder is built from.

    How is the tracking score calculated?

    Your score is how many of the ladder’s steps you clear before a second miss, and how many balls that was. To rank it, each of the 636 adults in Treviño et al. (2021) was put through the same ladder using their own trials at the same number of targets and speeds, with the same rules, so the percentile compares like with like. They played fixed paths and you play random ones, so it is close rather than exact.

    Does age affect how many things you can track?

    Yes, on average. Replayed through this test’s ladder, the people in Treviño et al.’s (2021) data aged 18–24 cleared 2.3 steps on average, those aged 35–49 1.9, those aged 50–64 1.7 and those 65 and over 1.1. The oldest group had only 27 people, so its figure is the least certain.

    Is a phone or a computer better for the tracking test?

    Either works. In Treviño et al.’s 2021 data, replayed through this test’s ladder, 28% of the 167 people who took the test on a phone cleared all three study steps, against 36% of the 469 on a computer. The data can’t say whether the screen caused the gap, but a bigger screen and good light are worth having.

    Is this an ADHD test or an IQ test?

    No. A multiple object tracking test measures one narrow skill, following moving objects with your attention for a few seconds. It does not diagnose attention disorders, check eyesight or measure intelligence, and one short run is too noisy to say anything about your health.

    Why did I get a different result the second time?

    A run is six short trials at most, and one slip where two balls cross can end it a step early. Tiredness, screen size and light also move the result. A few runs tell you more than one, and the pattern across them is closer to how many you can really track than any single run.

    Where the numbers come from

    The percentiles, the median, the averages, the best 5% and the age and device figures were computed for this test from the published trial-level data of the 636 adults in Treviño et al. (2021), by replaying each person’s own trials through this test’s ladder with the same rules as yours. Nobody in the study played a ladder, and the tray, paths and screens differ, so the comparison is close, not exact. The site does not publish its own players’ data.

    How the score is worked out

    The ladder

    Five steps, one more ball each; the speed rises once, after step 1. One trial with every target found clears a step; a miss gets a second try at the same step, a little faster; the second miss in the run ends it. No step takes more than two trials.

    Your result

    The steps you cleared, and how many balls you held on the highest of them. Bonus steps 4 and 5 go past what the study measured; a run that reaches them ranks as clearing all three study steps.

    Percentile

    Each of the 636 adults in Treviño et al. (2021) is put through the same ladder using their own recorded trials at the matching number of targets and speeds, with the same two-misses rule. Your percentile is the share of them who cleared fewer steps than you; ties count as half.