Lux ↔ ANSI Throw Converter

Quickly translate between illuminance readings and ANSI FL1 throw distance for flashlight measurements.

Lux to ANSI Throw

Measured illuminance (lux)

Measurement distance (meters)

Use 1 meter for standard candela readings.

Candela — ANSI throw distance —

ANSI throw distance (meters)

Distance for lux reading (meters)

Lux will scale with distance squared (inverse-square law).

Candela — Lux at chosen distance —

ANSI FL1 defines throw as the distance where beam intensity falls to 0.25 lux. Candela = lux × distance² and throw = √(candela ÷ 0.25).