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Relativity

Gravitational Time Dilation Calculator

Calculates how gravity slows time near massive objects using Einstein's general relativity. Use it when comparing elapsed time at different distances from a planet, star, or black hole.

Fill in the required fields to see your result.
Relativity

Relativistic Doppler Shift Calculator

Calculates the observed frequency of light or sound when source and observer move at relativistic speeds. Use it when relative velocity is a significant fraction of the speed of light.

Fill in the required fields to see your result.

Key differences

Gravitational Time Dilation CalculatorRelativistic Doppler Shift Calculator
CategoryRelativityRelativity
Inputs required33
ResultTime at Infinity (hours)Observed Frequency (Hz)
What it doesCalculates how gravity slows time near massive objects using Einstein's general relativity. Use it when comparing elapsed time at different distances from a planet, star, or black hole.Calculates the observed frequency of light or sound when source and observer move at relativistic speeds. Use it when relative velocity is a significant fraction of the speed of light.