A minimalist freehand circle challenge — draw a circle by hand and get an instant 0–100 roundness score, right in your browser. Free, no signup, fully private.
Try it Free →Your circle is scored 0–100 in real time based on how even the radius stays around its center.
Half-circles and short arcs can't fool the score — full 360° coverage is required to rate high.
The pen glows and shifts color with your accuracy, from red to gold-green as you near perfection.
When you finish, the perfect circle is overlaid as a dashed guide so you can see exactly where you drifted.
Hit 90+ and celebrate with a burst of confetti — then chase your personal best.
Everything runs in your browser. No uploads, no signup, and your best score is saved locally.
Press down anywhere on the blank canvas with your mouse or finger — an anchor dot marks your start point.
Move in a smooth circular motion. The score updates live and the stroke changes color with your roundness.
Bring the line back near the start point — the round ends automatically and locks in your final score.
Compare against the overlaid ideal circle, then tap Try Again to improve your high score.