Laser Divergence Calculator

This laser divergence calculator can quickly tell you how large a laser’s dot will become for a given distance and divergence. Enter the specifications of your laser in the fields below to see how the beam will diverge.

Enter laser specifications to calculate the divergence of a laser over a given distance.

Laser divergence is a measure of how much a laser beam spreads out as it travels over distance. It is typically measured in milliradians (mrad), which is a unit of angle. A milliradian is equal to 0.001 radians. A small divergence angle results in a more collimated beam which stays narrow over a greater distance, while a larger divergence angle results in a beam that spreads out more quickly over distance.


Looking to convert between wavelength and frequency?
Try the Wavelength to Frequency Calculator.