Size Comparison

A size comparison puts things of very different scale on one chart so their sizes can be judged against each other and against a person. Reading that a giraffe is about five and a half metres tall tells you less than seeing one drawn next to an adult; the same is true of a shipping container, a goal post or a skyscraper.

HeightViz draws every subject on one linear scale from a shared ground line. Nothing is exaggerated to fit: if one subject is three times the height of another, it is drawn three times as tall. When the tallest subject reaches 10 metres the rulers switch to metres, and the feet-and-inches ruler on the opposite side always shows the same heights.

1. Select Search the catalog and type a name, or pick a category such as Animals or Buildings to browse everything in it.
2. Choose Add on a result. Its name, height and source appear on the board; the height itself cannot be edited because it is a sourced fact.
3. Add a person for scale with the Male or Female button and set their height, or start from one of the popular comparisons in the rail.
4. Hover over the board to read any height off the scale, and pick two subjects below the chart to see the exact difference between them.
5. Select Share to copy a link that rebuilds the board, or Download to save it as an image.

“Height” means different things for different subjects, so every catalog record says exactly what was measured. Animals are usually listed at the shoulder when they stand on four legs and at the top of the head when they stand upright, which is why an elephant's figure is its shoulder height. Sports equipment uses the height written in the sport's rules, such as the top edge of a basketball rim. Buildings use the height their operator or a recognised authority publishes, and the note says whether antennas or a pedestal are included.

Many animals vary a great deal between individuals and between males and females. The board uses the adult figure the source gives, typically the upper end of a range, and the note records the range so you can judge how typical the figure is. Widths are illustrative until each entity has its own drawing; only heights are to scale.

Everything you can add to the board is listed here with its measurement and source. Heights are shown in metres from 10 metres upwards, as they are on the board.

The animal drawings come from PhyloPic, a library of open-licence silhouettes. Where a drawing's highest point is not the measured point (a lion's raised head above its shoulder), the board draws the animal to its measured height and marks that point with a dashed line.

Popular pairs have pages of their own with both sources and the computed difference: Human vs Giraffe, Human vs Elephant, Human vs T. rex, Human vs Lion, Human vs Gorilla, Human vs Polar Bear. See all of them on the comparisons index, or browse the animals and objects directories.

Only people are compared on the Height Comparison tool and the Height Comparison Chart; this page is where the rest of the catalog lives.