About the Age on Other Planets
Your age is simply the number of times your planet has gone around the Sun since you were born. Move to Mars, where a year lasts 687 Earth days, and you are suddenly about half your age; on Mercury, with its 88-day year, you would be four times older. This calculator uses the real orbital periods of the eight planets and Pluto to convert your Earth age into planetary years, and works out the date of your next birthday on each world.
Because the calculation counts days from your date of birth, it is exact for Earth and the other planets alike. Add your weight to see how it would change under each planet's surface gravity: you would weigh a little more than double on Jupiter and only 38% as much on Mars.
It is a favourite classroom activity for teaching orbits and gravity, and a fun fact to share on your birthday.
How to use the Age on Other Planets
- Enter your date of birth.
- Optionally enter your weight in any unit to see it converted for each planet.
- Read your age on Mars, Mercury and Jupiter, then explore the full table including your next birthday on each planet.