size it up.

A little perspective

Trust your eye.

Five comparisons. Two objects each time. How close can you get?

  1. Compare

    The object on the left is your measuring stick. Keep resizing — the view automatically zooms out when you need more room. You can also zoom the canvas; both objects scale together without changing your estimate.

  2. Find the right size

    Drag the blue handle, scroll while hovering it, tap − / +, or use the arrow keys. Match the dimension in the question.

  3. Lock it in

    Reveal the real size and earn up to 100 points. Five rounds add up to a maximum of 500.

The first answer in each round counts. A new challenge arrives every day at 00:00 UTC. Object sizes use the specific examples shown in the answer.

Read the full rules and scoring guideLet’s play

Classic

Size It Up archive

Another chance to test your intuition.

Replay past challenges as often as you like. Challenges and answers appear here after the UTC day ends at 00:00 UTC. Practice scores do not count toward any leaderboard or today’s progress.

Play today’s challenge

Past challenges

  1. 5 comparisons · practice & answers
  2. 5 comparisons · practice & answers
  3. 5 comparisons · practice & answers
  4. 5 comparisons · practice & answers
  5. 5 comparisons · practice & answers
  6. 5 comparisons · practice & answers
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  9. 5 comparisons · practice & answers
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  11. 5 comparisons · practice & answers
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  13. 5 comparisons · practice & answers
  14. 5 comparisons · practice & answers
  15. 5 comparisons · practice & answers