🔥
Streak: 0
Press down at center and drag outwards to draw radius
Circulo
Circle Area Estimation Game
A game of spatial geometry and size estimation. Can you scale circle areas accurately in your mind?
Baseline Circle:
A starting circle of random size is generated automatically.
Round 1:
Scale the random baseline circle's area by the target factor.
Rounds 2-5:
Scale the area of the
previously drawn (actual) circle
by the next factor.
(Note: estimation errors compound across rounds!)
Score:
The closer your drawn circle is to the mathematical target area, the higher you score! Get
90%+
for fireworks!
Begin Calibration
Practice
Circulo
Precision Estimation
ROUND 1: ESTIMATION
Draw a circle scaled by the target factor.
Drag out from the center dot to estimate the target size.
Current Radius
0px
Current Area
0 px²
Target Factor
Establish Baseline
Release to Set Circle
Circulo
Practice Sandbox
SANDBOX MODE
Practice scaling baseline circles here freely.
No round limits. Toggle guidelines for direct visual feedback.
Target Area Scale
1.50x
Show Guideline Ring
Radius Error
-
Precision Score
-
Exit
Release to Set Circle
Circulo
Round Breakdown
Round Score
95%
Exceptional spatial sense!
Target Area:
0 px²
Drawn Area:
0 px²
Target Radius:
0px
Drawn Radius:
0px
Area Error:
0.0%
Next Round
Circulo
Mission Complete
AVERAGE GAME SCORE
88.5%
Expert Geometer
Try Again
Share