What does Planetary Year Converter do?
Convert Earth years to orbital years for any planet — from Mercury's 88-day year to Neptune's 165-year orbit. Uses IAU standard orbital periods.
Orbital years
Convert orbital years (one trip around the Sun) between planets. For rotation days (length of a day), use the Planetary Day Converter (rotation vs orbit).
Instant answers
- 1 Jupiter year ≈ 11.86198494 Earth years
- 1 Mars year ≈ 1.880903491 Earth years
- 1 Saturn year ≈ 29.45713895 Earth years
- 1 Mercury year ≈ 0.2408487337 Earth years
Quick orbital-year presets
Tap a card to load the calculator with that planet pair and 1 year. URLs update so you can bookmark or share.
Orbital period (one year) in Earth days
Each value is roughly how many Earth days one full orbit takes—used for all conversions on this page.
| Planet | Orbit (Earth days) |
|---|---|
| Mercury | 87.97 |
| Venus | 224.7 |
| Earth | 365.25 |
| Mars | 687 |
| Jupiter | 4332.59 |
| Saturn | 10759.22 |
| Uranus | 30688.5 |
| Neptune | 60182 |
| Pluto | 90560 |
Orbital year calculator
Non-negative number; comma or dot as decimal separator.
1 Mars year ≈ 1.880903491 Earth years
Your amount in every planet's years
For 1 Mars year, here is the equivalent in each planet's orbital year (rounded for display).
| Planet | Equivalent years |
|---|---|
| Mercury | 7.809480505 |
| Venus | 3.05740988 |
| Earth | 1.880903491 |
| Mars(from) | 1 |
| Jupiter | 0.1585656616 |
| Saturn | 0.06385221234 |
| Uranus | 0.02238623589 |
| Neptune | 0.01141537337 |
| Pluto | 0.007586130742 |
Orbit vs day — same solar system, different question
Orbital year answers “how long is a year on this planet?” (one lap around the Sun). Sidereal day answers “how long is one spin?” (rotation). Jupiter’s year is many Earth years long, but its day is only about 10 Earth hours—both are useful, and we split them across this page and the Planetary Day Converter (sidereal rotation).
More solar-system tools
- Planetary Day Converter — rotation days between planets
- Age on Other Planets — your age in each planet’s years from your birth date
- Weight on Other Planets — surface gravity from your Earth weight
- Planet Distance Converter — AU, km, miles; mean Sun–planet distances
Quick glossary
- Orbital year (sidereal year)
- One full orbit around the Sun—the “year” we convert here, using each planet’s orbital period in Earth days.
- Sidereal day
- One full spin relative to distant stars. For day-length comparisons between planets, use our Planetary Day Converter.
- Synodic period
- Time between repeating alignments with Earth and the Sun (e.g. Mars opposition). This tool uses sidereal orbital periods, not synodic cycles—see the FAQs below for when that matters.