Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
EV at ISO 100
9.94
EV at your ISO
11.94
Shutter for the new aperture
1/500 s
Shutter with the ND filter
1/125 s
Approximate scene illuminance (lux)
2,450
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter aperture (f-number).
- 2Enter shutter speed denominator (1/x sec).
- 3Enter iso.
- 4Enter new aperture to match.
- 5Enter nd filter strength (stops).
- 6Read your ev at iso 100 on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Exposure value collapses aperture, shutter speed, and ISO into a single number, which makes it trivial to find equivalent settings or to see how many stops you are away from a target exposure.
Worked example
Using the values the calculator loads with:
Inputs
- Aperture (f-number): 5.6
- Shutter speed denominator (1/x sec): 125
- ISO: 400
- New aperture to match: 2.8
- ND filter strength: 0 stops
Results
- EV at ISO 100: 9.94
- EV at your ISO: 11.94
- Shutter for the new aperture: 1/500 s
- Shutter with the ND filter: 1/125 s
- Approximate scene illuminance (lux): 2,450
What each field means
Inputs
- Aperture (f-number)
- The aperture (f-number) used in the calculation. Starts at 5.6 so you have a working example on load.
- Shutter speed denominator (1/x sec)
- The shutter speed denominator (1/x sec) used in the calculation. Starts at 125 so you have a working example on load.
- ISO
- The iso used in the calculation. Starts at 400 so you have a working example on load.
- New aperture to match
- The new aperture to match used in the calculation. Starts at 2.8 so you have a working example on load.
- ND filter strength (stops)
- The nd filter strength used in the calculation, measured in stops. Starts at 0 stops so you have a working example on load. Accepted range: 0–20 stops.
Results
- EV at ISO 100
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- EV at your ISO
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Shutter for the new aperture
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Shutter with the ND filter
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Approximate scene illuminance (lux)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What is Sunny 16?
Bright direct sun is roughly EV 15 at ISO 100 — f/16 at 1/100 s. Every stop of shade or overcast drops it by one to four EV.
How do I use this for long exposures?
Meter normally, enter the ND strength, and read the ND shutter output. A 10-stop filter turns 1/125 s into about eight seconds.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Exposure Value (EV) Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/exposure-value
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/exposure-value" target="_blank" rel="noopener">Exposure Value (EV) Calculator — RevenueLab</a> (2026).</p>
Source: [Exposure Value (EV) Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/exposure-value) (2026).