Daily progress on this browser. Resets at 00:00 UTC; replays have separate saves.
Open scratchpadNotes stay on this page and are never submitted.
Your first round
How to play the size comparison game
The challenge is to match real-world proportions. A familiar reference gives you a starting point even when you have never seen the target in person.
01
Read the measurement
Check whether the question compares height, length, diameter or span. Keep the navy reference fixed and judge the target along the named axis.
02
Find the proportion
Begin with a rough bracket: half as big, about equal, or twice as big. Move the slider, use the − / + buttons, or drag the red target to refine your estimate.
03
Lock in and learn
Choose Lock in to reveal the true outline, dimensions and points. Continue through five rounds for a total out of 500.
Keyboard: focus the scale slider and use the arrow keys. Press Enter on the game board to submit or continue. All controls and game modes →
Build a sense of scale
Three comparisons to keep in mind.
These worked examples use the game’s measurements. Try each round before opening its answer, or explore the dimensions at your own pace.
Picture two buses end to end, then add about half a bus. This round uses a 29.9 m blue whale and a representative 12 m city bus; individual animals and bus models vary.
Start just above one quarter of Earth’s diameter. The Moon occupies a much smaller fraction of Earth’s volume, but diameter is the measurement this round asks you to judge.
Place both structures on the same ground line and aim below half height. The game counts the Eiffel Tower’s antenna and uses Burj Khalifa’s architectural height.
Ratios describe the named measurement. A silhouette twice as tall is not necessarily twice the area, volume or weight. Read the measurement conventions.
Every guess counts
How close is a good guess?
Each silhouette round awards up to 100 points. The score measures proportional error: an estimate twice the true size receives the same score as an estimate half the true size.
A small miss still earns useful points. Focus on the correct range first, then make smaller adjustments. These examples use the same scoring calculation as the playable board.
Daily Estimate and Survival use their own number-game rules.
Keep playing
Choose your next size challenge.
Category practice gives you another round after each reveal and leaves today’s result intact. Start with a subject you know, then try a less familiar scale.
A size comparison game tests how well you can judge one object against another. In Size It Up, you resize an unknown target beside a reference with a known measurement. Lock in your guess to reveal the correct proportion and earn a score.
Is this the Size It Up game by Magnitudle?
This is Size It Up Daily, an independent game at sizeitup.top with its own code, rounds and scoring. Magnitudle also makes a game called Size It Up. The sites are not affiliated, and their daily puzzles and results are different.
Can I play free on a phone without downloading an app?
Yes. Open this page in a modern mobile or desktop browser. Use the scale slider or the minus and plus buttons to resize the target. No account, app installation or payment is needed to play.
Does the daily game here share progress with the homepage?
Yes. This page and the homepage use the same daily game and browser save. Switching between them resumes your current round or completed result. Practice is separate and does not change your daily score or streak.
What can I do after today’s five rounds?
Choose unlimited practice for more comparisons, try Pop Culture or Geography, or replay a published date in the Archive. Each daily silhouette game is selected at 00:00 UTC; the daily rounds are the same for everyone on this site.
How is the game different from a size comparison tool?
In the game you estimate first and see the dimensions after submitting. A comparison tool lets you select two objects and inspect their known measurements immediately. Our Object Library supports that open-ended comparison, with measurement notes and links back to practice.
Help us improve the game?
With your permission, we use Google Analytics to understand which pages and game features are useful. The game works the same if you decline. Privacy details