☀️ Exposure Value (EV) Calculator
Enter an aperture, shutter speed and ISO to get the exposure value — and a table of equivalent settings that expose the same.
Exposure value (EV, at ISO 100)
EV 9.9
| Aperture | Equivalent shutter (same exposure) |
|---|---|
| f/1.4 | 1/500 s |
| f/2 | 1/245 s |
| f/2.8 | 1/125 s |
| f/4 | 1/61 s |
| f/5.6 | 1/31 s |
| f/8 | 1/15 s |
| f/11 | 1/8 s |
| f/16 | 1/4 s |
Exposure value EV = log₂(N²⁄t) at ISO 100 (N = f-number, t = shutter seconds); higher ISO lowers the scene EV needed. Each "stop" doubles or halves the light. The table lists equivalent aperture/shutter pairs that give the same exposure — trade depth of field against motion blur. 🔒 In your browser.
How the exposure value (ev) calculator works
Exposure value combines aperture and shutter into one number: EV = log₂(f-number² ÷ shutter time), quoted at ISO 100, with higher ISO lowering the light needed. Because it's a base-2 logarithm, each whole EV is one "stop" — a doubling or halving of light. The tool lists aperture/shutter pairs that all produce the same exposure.
The equivalent-exposure table is the heart of the exposure triangle: open the aperture and you must speed up the shutter to match, trading depth of field against motion blur. Every row captures the same total light.
Frequently asked questions
What is exposure value (EV)?
A single number combining aperture and shutter speed: EV = log₂(f-number² ÷ shutter seconds) at ISO 100. It measures how much light a given exposure lets in — higher EV means less light (bright scene).
What is a "stop" in photography?
A doubling or halving of light — one whole EV. Opening the aperture one stop, halving the shutter time, or doubling the ISO each change the exposure by one stop.
What are equivalent exposures?
Different aperture/shutter combinations that let in the same total light, so the photo is equally bright. For example f/8 at 1/125 and f/4 at 1/500 are equivalent — the tool lists them for your settings.
How does ISO affect exposure value?
Doubling the ISO makes the sensor twice as sensitive, so you need one stop less light — it lowers the scene EV required by 1 for each doubling. The EV shown is normalised to ISO 100.
How do I use the exposure triangle?
Balance aperture (depth of field), shutter (motion), and ISO (noise) to reach the exposure the scene needs. If you open the aperture for blur, speed up the shutter to keep the same brightness — that's what the equivalents show.