Mini Games
Find the Center
Click the exact mathematical center of a circle. A one-shot visual perception game scored to 0.01%.
How to play
- Tap Start. A circle of random size appears in a random spot.
- Click or tap where you think the exact center is — one shot only.
- Your point and the real center show up. Closer = higher accuracy (%).
My Best
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Aim for Eagle Eye!
Ranking
| Rank | Nickname | Score |
|---|---|---|
| Rank | Nickname | Score |
|---|---|---|
- |  You | - |
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Find the Center is a one-click visual perception mini-game where you must locate the exact mathematical center of a randomly sized circle. Even with a crisp edge to anchor your eye to, raw intuition rarely gets you past 99%. The moment you click, the distance between your click point and the true center, relative to the circle's radius, is converted into an accuracy score from 0 to 100%, displayed to two decimal places. One shot, one decision — that is the entire game.
The rules are minimal. There is no time limit, so take a breath, hover your cursor (or finger) over the circle, and let your peripheral vision read the whole shape at once. A common trick is to close one eye or sit a little farther from the screen so the whole circle reads as a single shape. After you click, the true center is revealed, and your score is recorded on the global ranking automatically, and you can send a challenge link to dare a friend to beat it.
Vision researchers call this task "centroid estimation." Your visual cortex handles sharp-edged shapes quickly, but pinpointing an unmarked center still forces the brain to estimate a center of mass from the whole outline — a much harder computation. Because every pixel of error costs roughly 0.5–1.8 points, depending on the circle's size, a score around 99% is already elite.
Tips for a high score: (1) stop moving the cursor before clicking and use only tiny micro-adjustments; (2) balance the distance to the edge along both the horizontal and vertical axes; (3) play in stable, even lighting; (4) on mobile, the edge of a fingernail gives a more precise hit point than a fingertip pad.
Frequently Asked Questions
Q. Is 99.99% possible?
A. Practically, no. Your score is 100 × (1 − distance ÷ radius), shown to two decimals, and every pixel of error costs roughly 0.5–1.8 points depending on the circle's size. Around 99% is a realistic top score; 99.99% would take sub-pixel precision. Clicking outside the circle scores 0.
Q. Is every circle the same?
A. No. Every round, including one opened from a challenge link, generates a fresh position and size, so a challenge compares scores only.
Q. Can I play on a phone?
A. Yes. On a computer you click; on a phone or tablet you tap once, and the score uses the same formula. Because accuracy is measured relative to the circle's radius, a smaller screen does not count against you — but a fingertip covers more area than a cursor, so aiming with the edge of your fingernail helps.
Q. How are grades decided?
A. By accuracy alone: S (Eagle Eye) at 95% or higher, A at 85%+, B at 70%+, C at 50%+, and D below 50%. There is no time limit, so clicking fast does not earn extra points.