Global Mind Tests

Rotary Speed Matching Test

Measure speed perception, timing accuracy and visuomotor coordination

Match the Speed of Two Rotating Discs

This rotary speed matching test shows two rotating discs. The left disc is the reference. The right disc changes speed. Press Match now when both discs appear to rotate at the same speed.

Ready? Complete 8 rounds. Lower speed error is better.
Reference disc
Changing disc
0/8Round
Last error
Average error
Keyboard: Space / Enter = Match now

How to interpret your score

The main result is your average absolute speed error. A lower value means you reacted closer to the moment when the two discs had the same speed. Use your average across all rounds, not one lucky attempt.

What does this test measure?

It measures speed perception, visual comparison of moving stimuli, divided attention, timing accuracy and hand-eye coordination. The task is related to pursuit-tracking and anticipation-timing tests used in psychomotor research.

Why it matters for driving-like skills

Driving requires judging changing speed, distance and timing while reacting with the hands. This browser test is not a legal driver psychotest, but it gives a practical sample of how consistently you can compare motion and act at the right moment.

What skills can this improve?

Repeated practice may support cleaner visual attention, better timing control, and more stable response decisions under changing motion. For broader comparison, try Reaction Test Level 2, Flanker, and Symbol Digit Test.

What affects your results

Results can shift with screen refresh rate, browser timing, mouse/touch latency, fatigue, sleep, stress and visual focus. Compare results on the same device and browser. You can also read about sleep, stress and cognitive performance.

Tips for reliable results

  • Watch both discs, not only the changing one.
  • Do not spam-click; each round accepts one response.
  • Use the same device if you want to compare trends.
  • Keep the browser tab focused and avoid heavy background apps.

Scientific background

Rotary pursuit and pursuit-tracking tasks are commonly used to sample visual-motor coordination, while anticipation-timing tasks often use absolute error as a key measure. This online version adapts the idea into a browser-friendly speed-matching format.

FAQ

What is a good result?

For this online version, below 8 deg/s average error is strong, 8-16 deg/s is good, 16-28 deg/s is moderate, and above 28 deg/s means the match timing was inconsistent. These are practical in-site ranges, not medical norms.

Why does the changing disc sometimes feel equal for a moment?

The changing disc accelerates or slows through the reference speed. Your task is to catch the crossing point as closely as possible.

Is this the same as a professional driver psychotest?

No. Professional assessments use standardized equipment, controlled conditions and examiner interpretation. This is only for training and self-tracking.

Try also

For a broader driving-style profile, combine this test with Reaction Time Test, Reaction Test Level 2, Poppelreuter Tables, and Flanker Test.

For training and self-tracking only; not a clinical, diagnostic or legal driving assessment.