Satellite Pass Predictor Calculator

Estimate satellite pass parameters including duration, max elevation, Doppler shift, and orbital period for amateur radio satellites.

Orbit Altitude

Orbital Inclination

Your Latitude

Minimum Usable Elevation

Tab to move between fields

Orbital Period

100.72 min

Max Pass Duration

15.3 min

Usable Pass Duration

9.7 min

Orbits per Day14.3

Orbital Velocity7.46 km/s

Visibility Footprint3,038 km

Max Range (Horizon)3,291 km

Max Doppler (146 MHz)3.63 kHz

Est. Passes/Day6

Overhead Distance800

How to Use This Calculator

Enter the satellite's orbital altitude (km) and inclination (degrees).
Set your station's latitude and the minimum usable elevation angle (typically 5–15°).
Review calculated orbital period (min), orbits per day, and maximum pass duration.
Use usable pass duration and passes per day to plan satellite operating schedules.
Higher elevation angles reduce pass duration but provide stronger signals with less multipath.

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Formula

T = 2π√(a³/μ); v = 2πa/T

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