Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Time Dilation Calculator (Velocity)

Calculates the dilated (coordinate) time experienced by a stationary observer when a moving clock ticks off a given proper time at relativistic speeds. Essential for understanding special relativity and GPS corrections.

Proper Time (years)

Relative Velocity (c (speed of light))

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.

Rest Frequency (Hz)

Relative Velocity (m/s)

Direction

Fill in the required fields to see your result.

Key differences

	Time Dilation Calculator (Velocity)	Relativistic Doppler Shift Calculator
Category	Relativity	Relativity
Inputs required	2	3
Result	Dilated Time (time units)	Observed Frequency (Hz)
What it does	Calculates the dilated (coordinate) time experienced by a stationary observer when a moving clock ticks off a given proper time at relativistic speeds. Essential for understanding special relativity and GPS corrections.	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.