What Is Size It Up?
Size It Up is a free online size guessing game that turns everyday questions about real-world scale into a quick visual challenge. A black silhouette sits on the board at its true size as your fixed reference. A white silhouette is yours to resize until the two look right next to each other. Lock in your guess and the truth appears in red—showing the actual measurement, how far off you were, and a score based on accuracy.
Most players underestimate a blue whale next to a school bus or misjudge the height of the Eiffel Tower. That surprise is the heart of the game. Five rounds make up the daily challenge, the same for everyone, refreshed at midnight in your time zone.
Highlight Features
- Daily Challenge with the same five silhouettes for every player
- Unlimited Mode for random pairs from the full library
- Geography Mode for countries, US states, and lakes
- Accuracy-based scoring up to 100 points per round
- Shareable result cards that never spoil the answers
- No account required—play instantly in your browser
How to Play Size It Up
Each round follows the same simple loop.
Compare, Resize, and Lock In
Start with the black reference silhouette and the ruler showing its real measurement. Use it as your scale guide.
Slide across the board or pull the white silhouette’s corner handle to resize it. On mobile, pinch to scale. Zoom the board out when the object is enormous.
When the proportions feel right, press Lock in. The true outline draws over your guess in red, revealing the real size, the percentage you missed by, and your round score. Complete all five rounds for the day’s total.
Game Controls
PC
- Mouse / Drag: Resize the target silhouette
- Corner Handle: Fine-tune the size
- Arrow Keys: Make small adjustments
- Enter: Lock in your estimate
Mobile
- Drag / Pinch: Resize the silhouette
- Tap Lock In: Submit your answer
Tips to Play Better
- Think in ratios instead of exact numbers—ask how many reference lengths would fit across the mystery object.
- Use familiar anchors: a bus is about 12 metres, a person roughly 1.7 metres.
- Extremely large or tiny subjects are easiest to misjudge, so compare both length and overall shape.
- Practice in Unlimited Mode to sharpen your eye before the daily challenge.
- Size It Up turns “how big is that, really?” into a fast, shareable puzzle that keeps surprising players with every red outline.