Size Comparison Game
5 ROUNDS A DAY · 1221 OBJECTS IN TODAY’S MIX
ROUND1 / 5
0 / 1,000
Preparing your round…
01 / Start with a silhouette
What is the Size Comparison Game?
Start with two silhouettes: a dark reference with a known measurement, and a light object whose size you control. Adjust the light shape until the pair looks right at a shared scale. Read the measurement axis first; comparing a whale’s length with a person’s height calls for more than matching their outlines.
The reviewed library currently contains 1,221 active objects.
02 / Read, resize, reveal
How to play the Size Comparison Game
Keep the reference fixed and resize the light silhouette to make your estimate. A round is worth up to 100 base points. The five Daily rounds have weights of 1, 1, 2, 3 and 3, giving a maximum of 1000 points. You can return to an unfinished set in this browser and continue from your saved round.
Read the reference
Read the reference’s name, version and axis to understand what its number measures.
Resize the guess
Move the resize handle or use the size controls. Zooming only changes the view.
Lock in
Submit your estimate to see the correct scale and points, then continue to the next round.
03 / A field guide to scale
Size comparisons at true scale
Each of these six examples uses one linear scale for both subjects. The red measurement lines show the span being compared, and the links specify the object and its dimension. These are worked examples rather than Daily answers. Fictional objects refer to the named version and its published size.
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
Small insects and stars cannot fit usefully on the same linear drawing. The nominal diameter of the Sun is roughly 1.07 × 10¹¹ times the length of this worker honeybee. At a scale large enough to show the Sun, the bee would be invisible.
Here, each band represents a tenfold change in metres. The marker shows where the example falls on that logarithmic band; the accompanying icon is only an identifier. Twelve bands cover the examples across eleven orders of magnitude, without implying that consecutive objects are exactly ten times apart.
- 5 cm
Chess pawn · height - 25 cm
Balloon whisk · length - 43 cm
Rolling pin · length - 65 cm
African penguin · height - 1.7 m
Emu · height - 8 m
Ankylosaurus · length - 184.4 m
Space Needle · height - 330 m
Eiffel Tower · height - 540.8 km
Uruguay · height - 1,638 km
Vietnam · height - 4,879 km
Mercury · diameter - 139,800 km
Jupiter · diameter
05 / Name the dimension
What the Size Comparison Game measures
Every round names a dimension: length, height, width, wingspan or diameter. Country and state outlines use a horizontal or vertical span, not surface area. Fictional subjects also specify a version, because a different model, form or adaptation may have a different stated measurement.
A shape enlarged twice along every axis has twice the length, four times the area and eight times the volume. This game asks about the named linear dimension. Earth and Jupiter use mean diameter; the Sun uses nominal diameter. Mount Everest uses elevation above sea level, which is different from the visible silhouette’s base-to-peak span.
2× length
4× area
8× volume
06 / The same miss in either direction
How the Size Comparison Game scores a guess
Scores follow the ratio between a guess and the real measurement. A guess at half the correct size and a guess at twice that size each earn 45 base points. Within a factor of 1.06 the score is 100; a factor of 5 or more in either direction earns zero.
The “off by” percentage answers a different question: how large is the difference relative to the actual size? Half-size is 50% off, while double-size is 100% off. Move over the graph, use its arrow-key controls, or open the table to explore how these readouts relate.
Size Comparison Game scores by guess ÷ true size. Move across the curve, or focus it and use the arrow keys.
100 pointsExact size · Error 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× | 100 | 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
Pick a familiar subject and open its Daily puzzle or an Unlimited set. The ranges below come from the active library and include reference objects. For planets and stars, read whether the stated measurement is a mean, nominal or estimated diameter.
Animals size comparison game: 162 objects, from Tardigrade: 0.05 cm · length · (adult) to Blue Whale: 27.4 m · length · Published upper-end total length, measured from snout to tail tip; not standing height..
The label identifies body length, standing height or wingspan. Unlimited practice
Insects
Bees, beetles, butterflies and mantises. Compare tiny bodies and surprisingly broad pairs of wings.
TODAY’S PUZZLE · 5 ROUNDS
Browse all materials →Insects size comparison game: 82 objects, from Booklouse: 0.1 cm · length · Head to abdomen tip; antennae and legs excluded. to Queen Alexandra's Birdwing: 26 cm · wingspan · Furthest left to furthest right wingtip with wings spread..
Body length and open wingspan measure different parts of an insect. Unlimited practice
Dinosaurs size comparison game: 93 objects, from Compsognathus: 70 cm · length · Selected published estimate of total body length, snout to tail tip; schematic reconstruction, not a specific measured specimen. to Diplodocus: 26 m · length · Selected published estimate of total body length, snout to tail tip; schematic reconstruction, not a specific measured specimen..
The label identifies body length, standing height or wingspan. Unlimited practice
Nature size comparison game: 43 objects, from Common dandelion: 10 cm · height · Representative standing height chosen within the published range; not a measurement of this individual. to Grand Canyon: 446 km · length · The horizontal axis represents cumulative Colorado River distance from Lees Ferry to Grand Wash Cliffs. The winding ribbon is a river schematic, not a geographic route trace; its bends and thickness do not measure rim width or canyon depth..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Countries size comparison game: 179 objects, from Singapore: 20.382 km · height · North-south extent of the displayed map: WGS84 meridional distance between its southernmost and northernmost boundary coordinates, not travel distance or elevation. All polygon parts assigned to this country in the pinned Natural Earth admin-0 feature. to Canada: 4,618.278 km · height · North-south extent of the displayed map: WGS84 meridional distance between its southernmost and northernmost boundary coordinates, not travel distance or elevation. All polygon parts assigned to this country in the pinned Natural Earth admin-0 feature..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Celestial bodies size comparison game: 14 objects, from Pluto: 2,376.6 km · diameter · Mean diameter: twice the published radius. Circular scale diagram, not a surface map or an exact limb model. to Jupiter: 139,822 km · diameter · Mean diameter: twice the published radius. Circular scale diagram, not a surface map or an exact limb model..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Buildings & landmarks size comparison game: 89 objects, from Moai: 4 m · height · Average height of the moai rather than any one statue. Side profile of the head and torso; the width is schematic. to Channel Tunnel: 50.5 km · length · Horizontal extent represents the full tunnel length in a straightened diagram, not a geographic map or a bore diameter..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Vehicles
Aircraft, ocean liners, rockets, cars and buses. Judge a Boeing 747, Titanic or Porsche by its outline.
TODAY’S PUZZLE · 5 ROUNDS
Browse all materials →Vehicles size comparison game: 94 objects, from Segway MAX G2: 1.21 m · length · Unfolded scooter; overall horizontal length, not handlebar height. to Seawise Giant: 458.45 m · length · Ultra large crude carrier, later Jahre Viking and Knock Nevis; length overall, bow to stern..
Most vehicles use length; upright vehicles may use their height. Unlimited practice
Household & everyday items
Compare the marked dimension.
TODAY’S PUZZLE · 5 ROUNDS
Browse all materials →Household & everyday items size comparison game: 96 objects, from microSD Card: 1.5 cm · length · (15 × 11 mm) to Roadside Phone Booth: 2.515 m · height · Representative size from a documented example; this generic silhouette is not a model-specific drawing..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Entertainment items size comparison game: 41 objects, from Six-sided Die: 1.6 cm · width · (16 mm) to Concert Grand Piano: 2.7 m · length.
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Technology & electronics
Compare the marked dimension.
TODAY’S PUZZLE · 5 ROUNDS
Browse all materials →Technology & electronics size comparison game: 55 objects, from AirPods Pro 2 earbud: 3.09 cm · height · Representative size from a documented example; this generic silhouette is not a model-specific drawing. to Sony BRAVIA XR-55A80L — TV without stand: 1.227 m · width · Representative size from a documented example; this generic silhouette is not a model-specific drawing..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Sports equipment & facilities
Compare the marked dimension.
TODAY’S PUZZLE · 5 ROUNDS
Browse all materials →Sports equipment & facilities size comparison game: 105 objects, from Squash ball: 4 cm · diameter · Representative midpoint of published 39.5–40.5 mm diameter range to Football Pitch: 105 m · length · (Soccer, FIFA size).
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Food size comparison game: 85 objects, from Gumdrop: 1.905 cm · diameter · Full outside diameter across the centre, not slice thickness. to Baguette: 54.61 cm · length · Straight end-to-end span; exclude decorative stems and leaves..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Fictional worlds size comparison game: 41 objects, from Harry Potter’s Wand: 35.5 cm · length · Official shop replica is approximately 35.5 cm long; this is not the eleven-inch wand measurement from the novel. to Imperial Star Destroyer: 1.6 km · length · Official Databank overall length; top-view illustration uses the horizontal nose-to-tail axis..
Check the measurement axis before comparing unfamiliar objects. Unlimited practice
Pokémon
Compare familiar Pokémon by their listed Pokédex height.
TODAY’S PUZZLE · 5 ROUNDS
Browse all materials →Pokémon size comparison game: 41 objects, from Ditto: 30 cm · height · Standard Pokédex height; the illustration is scaled to this value, not an anatomical measurement of its pose. to Dialga: 5.4 m · height · Standard Pokédex height; the illustration is scaled to this value, not an anatomical measurement of its pose..
Use the standard form and compare the marked height. Unlimited practice
08 / Carry a mental ruler
Tips for the Size Comparison Game
Build estimates around a few familiar measurements: an average adult at 1.71 m, a US interior door at 2.03 m, a school bus at 13.7 m, and Titanic at 269 m. First estimate how many references would fit along the target’s named dimension. Then use smaller adjustments to refine your guess.
For unfamiliar scales, check the label and endpoints before resizing. Landmark and celestial pairings are constrained to a factor of five in the current puzzle rules. Zoom lets you inspect the outlines without altering the guess; Unlimited gives you more chances to practise these comparisons.
09 / Guessing, exploring, learning
Other kinds of size comparison game
In a guessing game, you make an estimate before seeing the answer. This game uses that sequence in a daily set: inspect a reference, resize another object and receive a score with the correct comparison.
A scale explorer instead lets you browse dimensions freely, without asking for a guess or awarding points. Simple big-and-small activities introduce the idea of relative size. Choose the format that fits your purpose: browsing, learning the basics, or testing how closely you can estimate a measurement.
10 / Check the measurement
Size Comparison Game measurement sources
The active library contains 1,221 objects with recorded measurement and artwork sources. References include encyclopedias, astronomical data, official fictional specifications, standards and geographic outlines. Check the named version, axis and endpoints alongside the number. Retired entries stay in Credits for historical attribution but are excluded from current selection pools.
11 / Questions from the field
Questions about the Size Comparison Game
- What is the Size Comparison Game?
- Resize an object beside a known reference, submit your estimate, and compare it with the revealed measurement.
- Is the Size Comparison Game free? Do I need an account?
- Yes. Both Daily and Unlimited are available in your browser without creating an account.
- How is my score calculated?
- Each round awards up to 100 base points according to proportional error. The Daily weights are 1, 1, 2, 3 and 3, for a total of 1000 possible points.
- Why does “off by 50%” score the same as “off by 100%”?
- Half and double represent equal ratio errors, so each earns 45 points. The displayed percentage instead measures the difference as a proportion of the true size.
- Which dimension does each round compare?
- Use the labelled length, height, width, wingspan or diameter. Geography rounds compare an outline’s span rather than its area.
- How many objects and categories are there?
- The reviewed library currently contains 1,221 active objects.
- Is there a new puzzle every day, and can I keep playing?
- A Daily puzzle has five rounds. You can choose another category, open Unlimited for additional pairs, or visit Past Games to replay available earlier sets.
12 / Keep comparing
More ways to play
Choose a new Daily subject, practise with another set, or explore earlier puzzles.