Reflex · 30 targets, time and accuracy
Aim Trainer
Hit thirty targets as fast as you can. This aim trainer measures time to target and click accuracy — missed clicks count against you — and reports throughput in bits per second, the standard device-independent pointing metric. Most people average 600 to 800 ms per target with a mouse. Pick a target size and start.
Hit 30 targets as fast as you can
Each target appears the instant you hit the last one. Clicks that miss are counted against your accuracy, so do not spray.
Score
0
Mean
—
Best
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Accuracy
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Throughput
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Fitts's law
What the score is made of
Three readings that can move independently, and a composite that stops any one of them being gamed.
- Mean time to target— the interval from a target appearing to the click that hits it, averaged over the run. Raw speed, and the number most people mean by “aim”.
- Accuracy — hits divided by every click you made. Clicking empty space is a miss and is counted.
- Throughput — mean index of difficulty divided by mean time, in bits per second. This is the metric ISO 9241-9 standardized for comparing pointing devices, and it is the only one of the three that survives changing the target size.
- Score — (60000 ÷ mean ms) × (accuracy ÷ 100)² × 10. Accuracy is squared deliberately, so that clicking wildly costs more than it earns.
Fitts's law, with numbers
The Shannon formulation, from MacKenzie (1992): ID = log₂(D ÷ W + 1), where D is the distance the pointer travels and W the target width, both in pixels. The result is in bits. Doubling the distance adds about one bit; halving the target adds about one bit.
| Distance | Target width | Index of difficulty | Feels like |
|---|---|---|---|
| 200 px | 68 px | 1.98 bits | Trivial — the target is nearly under the cursor. |
| 400 px | 48 px | 3.22 bits | Moderate. One movement plus a short correction. |
| 600 px | 32 px | 4.30 bits | Hard. Expect two or more corrective sub-movements at the end. |
| 800 px | 32 px | 4.70 bits | Hard. Expect two or more corrective sub-movements at the end. |
A typical mouse user achieves somewhere between 3.5 and 5 bits per second. A trackpad is usually around a third lower, a touchscreen lower again for small targets and competitive with a mouse for large ones.
How to interpret your band
| Mean time | Band | What it means |
|---|---|---|
| 250–450 ms | Elite | Sub-450 ms per target with clean accuracy is competitive-shooter territory. |
| 450–600 ms | Strong | Fast, controlled movement — the corrective sub-movement is short or absent. |
| 600–800 ms | Typical | Where most people land with a mouse on a desktop display. |
| 800–1100 ms | Developing | Common on a trackpad. Input device explains more of this than skill does. |
| 1100+ ms | Deliberate | Accuracy is being prioritized over speed, or the pointer is a touchscreen. |
Aim is not reaction time
Roughly, aim time = reaction time + movement time. The first term is fixed by your nervous system and your hardware; the second depends on how far the pointer has to travel and how small the target is. Movement time is usually the larger share, which is why aim scores are two to three times reaction times.
Measure the first term on its own with the reaction time test, then subtract it from your mean here — the remainder is your movement time, and it is the part that practice actually improves. Mouse sensitivity matters more than most people expect: too low forces multiple corrective sub-movements, too high makes every approach overshoot.
Aim trainer questions
What does this aim trainer measure?
Three things. Time to target — how long between a target appearing and your click landing on it. Accuracy — hits as a share of all clicks, so missed clicks cost you. And throughput in bits per second, which combines speed with how difficult each movement actually was.
What is a good time per target?
Under 600 ms with clean accuracy is strong for a mouse on a desktop. Most people land between 600 and 800 ms. Under 450 ms is competitive-shooter territory. On a trackpad, add 200 ms or more before comparing yourself to anything — the input device dominates.
Why is my aim time so much slower than my reaction time?
Because they are different tasks. A reaction time test measures a fixed latency: one stimulus, one response, no movement. Hitting a target adds a ballistic movement across the screen plus corrective sub-movements at the end. Roughly, aim time = reaction time + movement time, and movement time is usually the larger share.
What is Fitts's law and why is it here?
Fitts's law says movement time grows with the log of distance divided by target width. The Shannon form used here is ID = log₂(D ÷ W + 1), measured in bits. It matters because a target that appears under your cursor is not the same task as one across the arena — without accounting for distance, a score would reward luck.
Why does missing count against me?
Because otherwise the optimal strategy is to click constantly and let one of them land, which measures nothing. Accuracy is squared in the score formula specifically so that spraying costs more than it gains.
Does the target size setting change my score?
It changes your raw time — smaller targets take longer, exactly as Fitts's law predicts. It changes your throughput far less, because throughput divides the difficulty of the movement by the time it took. That is the whole point of the metric: it is designed to be comparable across target sizes and devices.
Other instruments on this bench
- reaction time testFive trials on performance.now() with false-start detection, then median, mean and best against published norms.median ms · percentile
- online rulerCalibrated against a credit card (85.60 mm by ISO/IEC 7810), so centimeters are real centimeters on any screen.cm · fractional inches
- typing testTimed typing test with live caret, per-key error heatmap and net WPM computed from your own character counts.net WPM · accuracy %
- words per minute typing testThe WPM formula written out with your numbers substituted in, plus what each score means by profession.gross WPM · net WPM
Testing the hardware rather than the person? device tests — scroll, touch, refresh rate and input latency lives on a sister site. And if you want to see through someone else’s eyes rather than screen your own, use the simulate how an image looks to a protan, deutan or tritan viewer.