Laser Safety Calculator

Calculate MPE, NOHD, and required eyewear OD for laser safety analysis.

Laser safety analysis requires three key quantities: Maximum Permissible Exposure (MPE), the radiant power or energy density a human eye or skin can withstand without injury; Nominal Ocular Hazard Distance (NOHD), the minimum safe distance from an unobstructed beam; and required optical density (OD) of eyewear needed when working inside the NOHD. This calculator follows IEC 60825-1 and ANSI Z136.1 methodology for CW and pulsed beams, accounting for wavelength, pulse duration, aperture size, and viewing conditions. Use it to set up laser controlled areas, select protective eyewear, or verify safety parameters before working with an unfamiliar laser source.

MPE Inputs
Enter wavelength and exposure duration to calculate MPE.
Abridged Optics — Laser Safety Calculator v1.0Educational tool only — not a substitute for formal laser hazard analysis per ANSI Z136.1. Simplified MPE values may differ from standard tables. Always consult the full standard and your Laser Safety Officer.

All information, equations, and calculations have been compiled and verified to the best of our ability. For mission-critical applications, we recommend independent verification of all values. If you find an error, please let us know.