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Relativistic Velocity Addition Calculator

Computes the combined velocity of two objects moving at relativistic speeds, preventing any result from exceeding the speed of light. Use it when simple addition of velocities would violate special relativity.

Velocity 1 (m/s)

Velocity 2 (m/s)

Direction

Velocity Unit

Fill in the required fields to see your result.

Relativity

Relativistic Velocity Addition Calculator

Adds two velocities correctly under special relativity so the result never exceeds the speed of light. Essential when objects move at a significant fraction of c.

First Velocity (m/s)

Second Velocity (m/s)

Fill in the required fields to see your result.

Key differences

	Relativistic Velocity Addition Calculator	Relativistic Velocity Addition Calculator
Category	Relativity	Relativity
Inputs required	4	2
Result	Relativistic Sum (m/s)	Combined Velocity (m/s)
What it does	Computes the combined velocity of two objects moving at relativistic speeds, preventing any result from exceeding the speed of light. Use it when simple addition of velocities would violate special relativity.	Adds two velocities correctly under special relativity so the result never exceeds the speed of light. Essential when objects move at a significant fraction of c.