Calculator

Equivalent exposure calculator

Change aperture or ISO and get the shutter speed that keeps the same exposure, plus EV and lighting conditions.

Your metered (or known good) exposure

New settings — change aperture and/or ISO, we solve the shutter speed

Equivalent shutter speed—
Exposure value (EV₁₀₀)—
Light conditions—

How it works#

Exposure stays constant when N²/(t·ISO) stays constant. Each full stop of aperture (×1.4 in f-number) or doubling of ISO halves the required time.

Exposure value reference#

EV -6EV -4EV -2EV 0EV 2EV 4EV 6EV 8EV 10EV 12EV 14EV 16

Last updated October 03, 2026 · How we calculate · Sources