Size Comparison Game
Resize real objects. Trust your eye. See how close you get.
Opening your five comparisons…
Resize real objects. Trust your eye. See how close you get.
Opening your five comparisons…
Start a five-question practice round whenever you like. In each question, one object stays at a fixed size while you resize another on the same scale. Submit your estimate to see the real measurement, your error and your score before moving to the next comparison.
Compare animals, everyday objects, vehicles, buildings and planets. After a round, choose Keep practicing to start another five. Your last 20 comparisons will not repeat in a new practice round. Replaying a daily challenge gives you its original five questions.
Drag the target outline or its handle, move the slider, use the plus and minus buttons, or press the arrow keys for small changes. You can zoom or pan the canvas and use Fit both to bring the objects back into view. These view controls do not change your estimate.
Each guess earns up to 100 points, for a maximum of 500 per round. Guessing half or twice the actual size gives the same score. For measurements published as a range, a guess inside the range earns full points; outside it, the nearest boundary is used. Open the source after each answer to check the measurement.
Your current round, recent pairs and best practice score are saved locally when browser storage is available. You can refresh and continue, review all five answers after finishing, or share your score by pressing Share score. No account is needed, and records do not sync across devices.