Guides · 2026-07-02
How Old Would You Be on Mars? (And Every Other Planet)
A year is one trip around the Sun — and every planet takes a different time. Here's how to work out your age on Mars, Jupiter and beyond, with a free calculator.
Your age is really a count of how many times Earth has circled the Sun since you were born. Step onto another planet and that count changes completely, because every planet takes a different amount of time to orbit.
Your age on Mars
A Martian year lasts about 1.88 Earth years. To find your Mars age, divide your Earth age by 1.88. So a 30-year-old on Earth is only about 16 on Mars — you'd celebrate a birthday a little less than once every two Earth years.
The other planets
- Mercury (88 days per year): you'd be roughly 4× older than on Earth.
- Venus (225 days): about 1.6× older.
- Jupiter (11.9 years): most adults haven't had their first Jovian birthday yet.
- Saturn (29.5 years): a 30-year-old is barely 1 Saturn-year old.
- Neptune (165 years): almost nobody reaches their first birthday there.
Try it with your own birthday
Rather than doing the division by hand, pop your date of birth into the Age on Other Planets calculator and see your age on all eight planets at once. It's a fun, science-accurate way to grasp just how different a "year" is across the solar system.