Venus vs Mars
Venus (12,104 km) is 1.79× the size of Mars (6,779 km).
Mars is 56% of the height of Venus. The gap between them is 5,325 km (17,469,160 ft).
The comparison in numbers
| Thing | Size | In feet | Measured as |
|---|---|---|---|
| Venus | 12,104 km | 39,709,974 ft | diameter |
| Mars | 6,779 km | 22,240,814 ft | diameter |
What the scale shows
Venus (12,104 km) is 1.79× the size of Mars (6,779 km). The gap between them is 5,325 km (17,469,160 ft). Both are planets & moons, so the figures describe the same kind of thing.
Draw both on one baseline and the smaller one fills 56% of the frame while the larger one runs to the top. The two are close enough that the difference is easy to see side by side.
Read the rest — 8 more sections
What each figure means
The figure for Venus is its diameter (mean diameter). The figure for Mars is its diameter (mean diameter).
Crossing them
At a jet's 900 km/h, Venus's 12,104 km would take 13.4 hours and Mars's 6,779 km would take 7.5 hours.
In people: Venus is 7,119,765 adults of 1.7 m tall, Mars is 3,987,647.1. By size Venus is 7th of the 16 planets & moons on this site and Mars is 8th, so 1 place separates them in the ranking.
How to read these two figures
Before trusting any comparison, check what each number measures. Venus is given as a diameter, mean diameter. Mars is given as a diameter, mean diameter. Both are diameter figures, so putting them on one baseline is a like-for-like comparison, although the exact individual or convention still matters.
Worlds are listed by diameter. Gas giants are not round, so equatorial diameter is used for them and mean diameter for the rest. All figures are rounded from published mission data.
Where the pair sits among all the sizes here
Across all 86 things on this site, Venus is number 7 from the top and Mars is number 8. No other item falls between them, so in this collection they are direct neighbours.
Because the collection spans 13 mm up to 1,392,700 km, a ratio of 107,130,769,231× from smallest to largest, the position of a pair says a lot: both sit in the upper third of the list.
What the length ratio hides
A length ratio of 1.79× is easy to picture, but area and volume grow faster than length. If two objects had exactly the same shape, Venus would have about 3.19× the surface or footprint of Mars, and about 5.69× the volume. These two are not the same shape, so treat the figures as an upper bound for an imaginary scaled copy, not as a measurement of either one.
The drawing above shows length only. Mars is drawn 56% as tall as Venus, but the equivalent share of footprint would be only 31.4%, which is why the smaller one looks even slighter than the numbers alone suggest.
Time to cross each one
Light travels at 299,792,458 m/s, so it crosses Venus (12,104 km) in 40 milliseconds and Mars (6,779 km) in 23 milliseconds. A jet at 900 km/h would take 13.4 hours for the larger and 7.5 hours for the smaller.
These times assume a straight line and constant speed, which no real crossing has, but they turn a number in metres into something the body understands. At any fixed speed the travel times keep the same 1.79× ratio as the sizes.
The same figures in other units
Venus measures 12,104 km, which is 39,709,974 ft or 7,520.8 miles. Mars measures 6,779 km, which is 22,240,814 ft or 4,212.28 miles.
The difference between them is 5,325 km (17,469,160 ft). In kilometres the smaller one is 6,779 against 12,103.6, so the 1.79× ratio holds in every unit; only the numbers on the ruler change.
Questions people ask about this pair
Which is bigger, Venus or Mars?
Venus is bigger. At 12,104 km it is 1.79× the size of Mars, which is 6,779 km.
How many times does Mars fit along Venus?
Less than twice: Mars is 56% of the size of Venus, so one fits with 5,325 km to spare.
Are the two figures measured the same way?
Yes in kind: both are diameter figures. Venus is mean diameter; Mars is mean diameter.
How does the gap look in people?
Taking an adult of 1.7 m, Venus is about 7,119,765 people tall and Mars is about 3,987,647.1. The gap of 5,325 km is 3,132,118 people.
Where do the numbers come from?
Each item has its own page that names the measurement and links to the Wikipedia article it was taken from. Some figures are rounded, and animals vary from one individual to the next, so treat them as representative values rather than records for every case.
How the sizes are taken. Each figure says what it measures — height, length, diameter or elevation — and for which individual or convention. Everything is drawn standing upright on one baseline so a single scale holds, including things that are long rather than tall. Values come from the linked Wikipedia article for each item.