📸
Exposure Calculator
Enter your aperture, shutter speed, and ISO to calculate the resulting exposure value (EV).
f/
seconds
ISO
How exposure value (EV) is calculated
Exposure value (EV) is a single number that combines aperture and shutter speed to describe how much light reaches the camera sensor. It’s a standard way for photographers to compare exposure settings independent of the specific combination of aperture and shutter speed used.
The formula used is: EV100 = log2(Aperture² ÷ Shutter Speed), then adjusted for ISO sensitivity with EV = EV100 − log2(ISO ÷ 100), since higher ISO settings effectively require less light for the same visible brightness.
- Higher EV numbers mean less light is needed (bright scenes, fast shutter, small aperture).
- Lower EV numbers mean more light is needed (dark scenes, slow shutter, wide aperture).
- Enter shutter speed in seconds; for 1/125s, enter 0.008.
This tool is for general photography reference and educational purposes.
Last reviewed August 2026