PERCEPTION

Which Was Longer?

Two hidden intervals play back to back. Choose which one lasted longer. The game tracks your accuracy across rounds.

MULTI-ROUNDCOMPARISONSOLO

TIME COMPARISON

Two hidden time intervals. One simple question. Which one lasted longer?

Difficulty:

How to Play

1. Watch

Two hidden time intervals play. Focus on how long each one feels.

2. Compare

Choose: Was A longer, was B longer, or were they about the same?

3. Learn

See the real times and whether your judgment was correct.

How Accuracy Works

Unlike other timing games, Which Was Longer? doesn't measure milliseconds. Your score is based on how many comparisons you get right.

Answer speed does not affect your score. Only the correctness of your comparison matters. "The Same" is only correct when the two intervals differ by less than the difficulty tolerance.

Which Was Longer? FAQ

Is this a reaction time test?+

No. This game tests time comparison — how well you can judge relative durations. Reaction speed does not affect your score.

Does answer speed affect my score?+

No. Take as long as you need. Only the correctness of your choice matters.

What does "The Same" mean?+

It means the two intervals were close enough to be indistinguishable. The tolerance depends on the difficulty level.

How are the two intervals measured?+

Each interval uses browser performance.now() timestamps recorded after the START and STOP signals are visually rendered.

Can I play with friends?+

Yes! Pass the device around — everyone watches the same intervals, then answers privately.

Is this a cognitive or medical test?+

No. This is a casual browser game and entertainment tool, not a medical, psychological, or cognitive assessment.

Try another Stop the Timer game →Play Guess the Time →Try Reproduce the Time →

How This Mode Works

Two hidden intervals play one after another. You watch both without seeing any timer, then choose which one you think lasted longer. The game reveals the actual durations and tracks your accuracy across rounds. This tests your comparative time perception.

What Appears in Your Score

Your answer, correct answer, duration A, duration B, correct / incorrect, and running accuracy across rounds.