Lorentz Factor Calculator

About this calculator

This calculator finds the Lorentz factor γ from a speed (as a fraction or percentage of the speed of light): γ = 1/√(1 − v²/c²). This factor is central to special relativity — it determines time dilation (moving clocks run slow by a factor of γ) and length contraction (moving objects shrink along their direction of motion by a factor of 1/γ), and it grows without bound as v approaches c.

Physics students and researchers use it to work through relativistic problems in particle physics (where particles routinely reach speeds close to c in accelerators), astrophysics (relativistic jets, cosmic rays), and to understand why GPS satellite clocks need relativistic corrections. Enter a velocity as a fraction of the speed of light to get γ along with the resulting time dilation and length contraction factors.