Orbital Period Calculator
Calculate orbital period from semi-major axis (Kepler’s third law).
How it works
Fill in the 1 field above and Orbital Period Calculator calculates the result instantly, recalculating as you change any value. It applies the formula T = a^1.5 (years, AU). The math runs locally in your browser — nothing is sent to a server.
Formula
T = a^1.5 (years, AU)Examples
- Semi-major axis 1 AU → Orbital period: 1 years
Frequently asked questions
How do I use the Orbital Period Calculator?
Enter your values in the 1 input field and the result is calculated automatically as you type. Change any value to see the numbers update instantly.
What formula does the Orbital Period Calculator use?
It uses T = a^1.5 (years, AU). The calculation is performed in your browser using standard, well-established math for accurate results.
Is my data private?
Yes. The Orbital Period Calculator runs entirely in your browser. Nothing you enter is uploaded, saved to a server, or shared — it never leaves your device.
Is the Orbital Period Calculator free?
Yes, it is completely free with no sign-up, no limits and no watermarks. Like every tool on astronomy and the rest of the platform, you can use it as often as you like.
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