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Size Comparison Game
5 ROUNDS A DAY · 379 OBJECTS IN TODAY’S MIX
DailyNo. —
Turn your phone upright
The board needs the height.
Slide left or right anywhere on the board to resize the white silhouette. Arrow keys resize it a step at a time, Enter locks in your guess.
Slide anywhere on the board to resize · then Lock inSlide anywhere on the board to resize
Today’s five done Next puzzle in –:––:––
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Microscopic World
Bacteria, cells, pollen and tiny organisms — explore sizes under a microscope.
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01 / Start with a silhouette
What is the Size Comparison Game?
The Size Comparison Game puts unlike things side by side. A black silhouette is your reference; resize the cream silhouette until their measured dimensions match the real world. Each round compares a single dimension, so a long whale and a tall person need different mental rulers.
The Size Comparison Game is free, with no account needed. Choose Mixed or 10 categories drawn from 1028 active, sourced objects. Play 5 Daily rounds, then switch to Unlimited for more pairs. The Mixed puzzle above draws from its own 379-object pool.
02 / Read, resize, reveal
How to play the Size Comparison Game
In the Size Comparison Game, the reference stays fixed while you adjust your guess. Each round earns 0–100 points, for a Daily total of 500.
Read the reference
Check the object’s name, version and measurement axis before judging the gap.
Resize the guess
Drag the cream silhouette’s resize handle or use the size controls. Zoom changes your view, not your guess.
Lock in
Submit to reveal the real scale and your score. Continue through the Daily set; use Unlimited to practise.
03 / A field guide to scale
Size comparisons at true scale
These 6 Size Comparison Game examples use a shared scale within each card. Red lines mark the measured span; the captions name its definition. They are reference examples, not today’s answers. Fictional subjects use the stated size of the named version.
An X-wing is almost exactly as long as a US school bus (0.98×).
Snorlax would have to duck under this US door: its stated height is 1.03× the door height.
This adult blue whale is about 68% of the length of a Boeing 737-800.
Daitarn 3 stands about 1.3 Statues of Liberty tall, pedestal included.
Pluto is not even twice as wide as Texas: 1.91× its east–west outline span.
About 11 Earths would span Jupiter, using mean diameters.
04 / Across orders of magnitude
From a honeybee to the Sun
The Size Comparison Game spans familiar things and distant worlds. The Sun’s nominal diameter is about 1.07 × 10^11 times this worker honeybee’s length. A linear drawing would make the bee disappear.
Each band below covers a factor of 10 in metres, with an example placed at its actual logarithmic position. There are 12 bands across 11 orders of magnitude; neighbouring objects need not differ by exactly 10×.
- 10-2 mHoneybee: 1.3 cm · length · (Worker)
- 10-1 mSmartphone: 14.7 cm · height · (6.1-inch)
- 100 mHuman: 1.71 m · height · (Average Adult)
- 101 mSchool Bus: 13.7 m · length · (US Type C)
- 102 mRMS Titanic: 269 m · length
- 103 mMount Everest: 8.849 km · height · (above sea level)
- 104 mManhattan Island: 21.6 km · length · (end-to-end length)
- 105 mSwitzerland: 343.1 km · width · outline span (east–west), not area
- 106 mPluto: 2,376.6 km · diameter · (mean diameter)
- 107 mEarth: 12,742 km · diameter · (mean diameter)
- 108 mJupiter: 139,822 km · diameter · (mean diameter)
- 109 mSun: 1,391,400 km · diameter · (nominal diameter)
Logarithmic position in metres · 10-2 to 1010
05 / Name the dimension
What the Size Comparison Game measures
The Size Comparison Game labels the axis: length, height, width, diameter or wingspan. Geography uses the outline’s longest horizontal or vertical span, never its area. For Pop Culture, read the named version and its stated dimension.
Doubling every linear dimension gives 2× the length, 4× the area and 8× the volume of the same shape. Those are different questions. Here, Earth and Jupiter use mean diameters; the Sun uses nominal diameter. Everest is measured above sea level, not from the base of its silhouette.
2× length
4× area
8× volume
06 / The same miss in either direction
How the Size Comparison Game scores a guess
The Size Comparison Game scores proportional error. Half or double the true size both earn 45 points. A guess of 1.06× earns 100; reach a factor of 5 in either direction and the score is 0.
The game’s “off by” label measures linear error instead: half is off by 50%, double by 100%. The different percentages describe the same proportional miss. Inspect the curve or open its table to compare guesses.
Size Comparison Game scores by guess ÷ true size. Move across the curve, or focus it and use the arrow keys.
100 points Exact size · off by 0%
Size Comparison Game score table
| Guess ÷ truth | Score | Off by |
|---|---|---|
| 1/5× | 0 | 80% |
| 1/4× | 18 | 75% |
| 1/3× | 30 | 67% |
| 1/2× | 45 | 50% |
| 1/1.32× | 62 | 24% |
| 1/1.2× | 78 | 17% |
| 1/1.12× | 90 | 11% |
| 1/1.06× | 99 | 6% |
| 1.06× | 100 | 6% |
| 1.12× | 90 | 12% |
| 1.2× | 78 | 20% |
| 1.32× | 62 | 32% |
| 2× | 45 | 100% |
| 3× | 30 | 200% |
| 4× | 18 | 300% |
| 5× | 0 | 400% |
07 / Choose a familiar world
Play the Size Comparison Game by category
Choose a Size Comparison Game category below. Each card opens its Daily puzzle or Unlimited practice; its range includes reference objects. Celestial labels distinguish mean diameters, the Sun’s nominal diameter and estimated stellar diameters.
Animals
Blue whale, African elephant, giraffe, bald eagle, golden retriever, honeybee — animal against animal.
TODAY’S PUZZLE · 5 ROUNDS
Animals size comparison game: 120 objects, from Tardigrade: 0.05 cm · length · (adult) to Blue Whale: 27 m · length · (Average Adult).
Length, height or wingspan — every round names the axis. Unlimited practice
Geography
Brazil, France, Japan, Texas, Lake Baikal — countries, US states and lakes, outline against outline.
TODAY’S PUZZLE · 5 ROUNDS
Geography size comparison game: 301 objects, from Aruba: 21.233 km · height · outline span (north–south), not area to United States: 8,430.9 km · width · outline span (east–west), not area.
East–west or north–south span, never area. Unlimited practice
Pop Culture
Pokémon, Star Wars, Gundam, Godzilla and more — characters, creatures and ships at their stated size.
TODAY’S PUZZLE · 5 ROUNDS
Pop Culture size comparison game: 198 objects, from Golf Ball: 4.27 cm · diameter to Moon: 3,474.8 km · diameter · (Earth’s moon · mean diameter).
Check the version. Compare the measured dimension. Unlimited practice
Vehicles
Boeing 747, Titanic, Saturn V, Porsche 911, a London double-decker — measured end to end.
TODAY’S PUZZLE · 5 ROUNDS
Vehicles size comparison game: 84 objects, from Skateboard: 80 cm · length to Seawise Giant: 458.45 m · length · (supertanker).
Length end to end, or height for the ones that stand upright. Unlimited practice
Dinosaurs
Tyrannosaurus rex, Triceratops, Stegosaurus, Velociraptor, Spinosaurus — dinosaur against dinosaur.
TODAY’S PUZZLE · 5 ROUNDS
Dinosaurs size comparison game: 60 objects, from Compsognathus: 70 cm · length · Compsognathus longipes to Diplodocus: 26 m · length · Diplodocus carnegii.
Compare estimated body length, from snout to tail tip. Unlimited practice
Space
Jupiter, the Moon, Proxima Centauri and the Sun — compare planets, moons and stars.
TODAY’S PUZZLE · 5 ROUNDS
Space size comparison game: 60 objects, from Deimos: 12.4 km · diameter · (Mars’s moon · mean diameter) to HD 209458: 1,655,766 km · diameter · (estimated stellar diameter).
Compare body diameter. Rings and orbital distances are excluded. Unlimited practice
Everyday Objects
Smartphone, credit card, refrigerator, tennis racket, dartboard, SIM card — at their stated size.
TODAY’S PUZZLE · 5 ROUNDS
Everyday Objects size comparison game: 91 objects, from microSD Card: 1.5 cm · length · (15 × 11 mm) to Table Tennis Table: 2.74 m · length · (regulation).
Length, height or width — every round names the axis. Unlimited practice
Insects
Honeybee, monarch butterfly, praying mantis, stag beetle, bed bug — from millimetres to open wings.
TODAY’S PUZZLE · 5 ROUNDS
Insects size comparison game: 80 objects, from Booklouse: 0.1 cm · length · (adult) to Queen Alexandra's Birdwing: 26 cm · wingspan · (adult female · open wings).
Body length or wingspan — read the named measurement. Unlimited practice
Landmarks
Eiffel Tower, Burj Khalifa, Great Pyramid of Giza, Colosseum, Tower Bridge — at their real-world size.
TODAY’S PUZZLE · 5 ROUNDS
Landmarks size comparison game: 29 objects, from Brandenburg Gate: 26 m · height · (with the quadriga) to Burj Khalifa: 828 m · height.
Read the named height, length or main span — including its endpoints. Unlimited practice
Food & Drink
Baguette, croissant, spaghetti, strawberry, ostrich egg, wine bottle — at their stated size.
TODAY’S PUZZLE · 5 ROUNDS
Food & Drink size comparison game: 60 objects, from Cheese Cracker: 2.54 cm · width · (USDA square cracker · laid flat) to Baguette: 54.61 cm · length · (Bridor 6371, nominal finished size).
Read the selected size and axis — length, diameter or container height. Unlimited practice
08 / Carry a mental ruler
Tips for the Size Comparison Game
Keep a few Size Comparison Game anchors in mind: Human: 1.71 m · height · (Average Adult); Interior Door: 2.03 m · height · (US); School Bus: 13.7 m · length · (US Type C); RMS Titanic: 269 m · length. Estimate the multiple first, then fine-tune the silhouette along the named axis.
Landmarks and celestial bodies lack an everyday sense of scale. The Size Comparison Game therefore pairs them only within 5× of another object. This is a puzzle rule, not a claim about player performance. Use zoom to inspect a small outline, and Unlimited to build familiarity.
09 / Guessing, exploring, learning
Other kinds of size comparison game
A guessing game asks you to estimate a size before revealing it. The Size Comparison Game follows this pattern, with a daily challenge and feedback after each guess.
A scale browser lets you move between objects and explore their dimensions without a score. Early-years big-and-small activities teach basic comparisons. Choose exploration for browsing, simple activities for that first lesson, or the Size Comparison Game to test your own estimates.
10 / Check the measurement
Size Comparison Game measurement sources
The Size Comparison Game draws on 1028 active objects with source links: encyclopedias, NASA and IAU data, official fictional specifications, standards and Natural Earth outlines. Versions and axes matter as much as the number. Retired entries are excluded from these examples and current pools. See Credits for attribution, or report a questionable dimension through feedback.
11 / Questions from the field
Questions about the Size Comparison Game
- What is the Size Comparison Game?
- The Size Comparison Game asks you to resize a silhouette against a reference, then reveals the correct scale and your score.
- Is the Size Comparison Game free? Do I need an account?
- Yes, the Size Comparison Game is free. Daily and Unlimited work in your browser without registration.
- How is my score calculated?
- The Size Comparison Game scores the ratio between your guess and the true size, up to 100 points per round and 500 per Daily set.
- Why does “off by 50%” score the same as “off by 100%”?
- Half and double are the same multiplicative error. Both earn 45 points; “off by” instead reports linear percentage error.
- Which dimension does each round compare?
- Follow the axis shown in the Size Comparison Game: length, height, width, wingspan or diameter. A geographic outline compares span, not area.
- How many objects and categories are there?
- The Size Comparison Game has 10 categories plus Mixed, drawing on 1028 active library entries. The Mixed pool contains 379.
- Is there a new puzzle every day, and can I keep playing?
- Yes. The Size Comparison Game offers 5 Daily rounds. Unlimited continues with random pairs; Past Games opens earlier Daily sets.
12 / Keep comparing
More ways to play
Continue the Size Comparison Game in the mode that suits you.