Free Exposure Equivalence Calculator
Exposure value (EV) is a single number describing how much light a camera captures for a given aperture and shutter time at ISO 100. One exposure, many settings. Enter what your meter says, then find every aperture/shutter/ISO combination that captures the identical amount of light — the exposure triangle, without the guesswork.
Your current exposure
Result
Equivalent exposure pairs (same EV, full frame reference)
| Aperture | Shutter (at ISO 100) | EV100 |
|---|---|---|
| f/1.4 | 1/1000 s | 10 |
| f/2.0 | 1/500 s | 10 |
| f/2.8 | 1/250 s | 10 |
| f/4.0 | 1/125 s | 10 |
| f/5.6 | 1/60 s | 10 |
| f/8.0 | 1/30 s | 10 |
| f/11 | 1/15 s | 10 |
| f/16 | 1/8 s | 10 |
Each row captures the same amount of light (EV 10): closing the aperture one stop halves the light, so the shutter must double in length. This is the exposure triangle in its purest form. For the full explanation see the exposure triangle guide.
Worked example
You're shooting f/2.8 at 1/250 s, ISO 100 — the calculator reports EV ≈ 11. You want more depth of field: open to f/4 costs one stop of light, so the equivalent exposure becomes 1/125 s (one stop slower). Same EV 11, same brightness, twice the depth of field. That's the entire point of the tool: instead of guessing, set the aperture you want, read the shutter you need, and only reach for ISO when neither aperture nor shutter can move. In practice this kills the most common exposure error — changing one setting and forgetting to compensate the other.
Related tools & guides
Exposure Value Chart
EV ↔ stops ↔ light reference table.
Open →Shutter Angle Calculator
Convert angle to shutter speed for any frame rate.
Open →ND Filter Calculator
Find the ND strength for long exposures in daylight.
Open →Exposure value FAQ
What is exposure value (EV)?
EV = log₂(N²/t) — a single number describing how much light reaches the sensor for a given aperture N and shutter time t. EV100 is the EV at ISO 100. Higher EV = brighter scene or more light collected.
Do equivalent exposures look identical?
Brightness: yes. But each parameter changes the image: aperture changes depth of field, shutter changes motion blur, ISO changes noise. Equivalence lets you trade one for another while keeping brightness constant.
How does ISO fit into EV?
ISO doesn't change the light — it changes amplification. The scene-brightness value is EV100 − log₂(ISO/100): at ISO 400 (2 stops), the same scene reads as 2 EVs lower, which is why you can shoot at 1/4 the shutter speed or 2 stops narrower aperture.
Exposure value chart: what EV means in practice
Short answer: EV measures the light, not the camera settings. EV 15 is bright sun, EV 8 is a lit street at night, and each EV step is one stop of shutter, aperture or ISO. At ISO 100, EV = log2(N squared / t).
| Scene | EV at ISO 100 | Start at f/2.8 | Start at f/8 |
|---|---|---|---|
| Bright sun, clear sky | 16 | f/2.8 at 1/8000 | f/8 at 1/1000 |
| Sunny, hazy or thin cloud | 15 | f/2.8 at 1/4000 | f/8 at 1/500 |
| Cloudy bright, open shade | 14 | f/2.8 at 1/2000 | f/8 at 1/250 |
| Overcast | 13 | f/2.8 at 1/1000 | f/8 at 1/125 |
| Heavy overcast, deep shade | 12 | f/2.8 at 1/500 | f/8 at 1/60 |
| Sunset, sun on the horizon | 12 | f/2.8 at 1/500 | f/8 at 1/60 |
| After sunset, warm afterglow | 9 | f/2.8 at 1/60 | f/8 at 1/8 |
| Night street with lit signs | 8 | f/2.8 at 1/30 | f/8 at 1/4 |
| Full moon | 15 | f/2.8 at 1/4000 | f/8 at 1/500 |
| Milky Way, dark sky | 2 | f/2.8 at 2 s | f/8 at 15 s |
Read this as a sanity check. A grey card in bright sun sits at EV 15; snow and white sand need +1 to +2 EV of compensation because the meter wants to render them grey, and a dark forest or a backlit subject needs -1 EV.
One EV is one stop, so equivalent exposures share an EV: f/2.8 at 1/500 s, f/8 at 1/60 s and f/11 at 1/30 s are the same brightness. The calculator above converts between them without changing the exposure.