Your age is really just a count of how many times Earth has carried you around the Sun. But every planet orbits at its own pace, so your age would look wildly different from another world. This age on other planets calculator takes your birth date and shows how old you are on Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune.
What a "year" really means
One year is a single orbit of the Sun — and that takes a different amount of time on every planet. Mercury completes an orbit in just 0.24 Earth years, Mars in 1.88, Jupiter in 11.86, and Neptune in a leisurely 164.8. Because your birthdays are counted in Earth orbits, translating them to another planet is simply a matter of dividing by that planet's orbital period.
How the calculation works
The tool first works out your exact age in Earth years from your date of birth, then divides it by each planet's orbital period. So a 30-year-old is about 124 years old on Mercury, 16 on Mars, just 2.5 on Jupiter, and only 0.18 — not even a fifth of a year — on Neptune.
Oldest and youngest across the solar system
You are always oldest on Mercury, the fastest orbiter, and youngest on Neptune, the slowest. It is a striking reminder that while time feels universal, our way of measuring it — the year — is tied entirely to Earth's particular journey around the Sun.
Try it with your birthday
Enter your date of birth and every planet updates instantly. It is a fun way for students and space enthusiasts to explore orbital periods, and a great conversation starter — when is your next birthday on Mars?
Orbital periods are based on NASA planetary data; ages use an Earth year of 365.25 days.