Calculator

ND filter calculator

Shutter speed with 1–20 stop ND filters, with a built-in countdown timer for long exposures.

Metered shutter speed (no filter) ND filter

Shutter speed with filter—

Light reduction—

How it works#

New time = metered time × 2^stops. A 10-stop (ND1000, ND 3.0) filter multiplies time by 1,024.

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