Mechanical & Civil Engineering
Orbital Period Calculator
Determine orbital period and semi-major axis for an Earth-orbiting body using Kepler's third law.
Your inputs
Change any value to update the result instantly.
Orbital period
92.41 min
Semi-major axis
6,771 km
Orbital velocity
7.673 km/s
Period in seconds
5,544.9 s
Orbits per day
15.58
What this calculator does
Orbital Period Calculator: Applies the standard aerodynamics or orbital-mechanics relationship so the force, efficiency or manoeuvre cost can be worked out from the flight inputs.
What your result means
The headline figure is the aerodynamic force, efficiency or manoeuvre cost implied by your flight inputs. Real vehicles carry additional losses and margins.
Formula and working
T = 2π·√(a³/μ)
- 1
Collect the inputs
Orbital altitude = 400 km
- 2
Apply the formula
T = 2π·√(a³/μ)
- 3
Result
Orbital period = 92.41 min
Frequently asked questions
Symbols and assumptions
- altitude
- Orbital altitude (km)
- • Standard-atmosphere and idealised flow or two-body orbital conditions are assumed.
- • Losses, gravity turn, atmospheric drag and vehicle-specific effects are not modelled unless the page names them.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • This is an educational estimate for learning and checking, not a design deliverable.
- • Real design must follow the governing code or standard for your jurisdiction and be reviewed and signed off by a qualified engineer.
- • Safety factors, load combinations and material certification are the responsibility of the designer, not of this page.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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