Aperture (f-stop)
Calculate Aperture (f-stop) instantly with the exact formula and a worked example.
Aperture (f-stop)
Focal lengthmm
F-number f/N
Compare with f/N
Aperture opening area
250.4458mm²
Entrance pupil diameter
17.86mm
Difference from second aperture
2EV
Light ratio
4×
More about: Aperture (f-stop)
What it calculates
The “Aperture (f-stop)” calculator computes Aperture opening area in mm² from 3 parameters: focal length (mm), f-number f/n, compare with f/n.
Used by photographers and videographers when setting up a shoot.
Example calculation
With parameters Focal length = 50 mm, F-number f/N = 2.8, Compare with f/N = 5.6 the result is 250.45 mm².
How to use
- Enter focal length, f-number f/n and compare with f/n — each field above is adjustable with a slider.
- Aperture opening area (mm²) is calculated automatically as you type.
- Check the worked example below to see the formula applied to real numbers.
- Copy the result or bookmark this calculator.
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FAQ
How is Aperture (f-stop) calculated?
The Aperture (f-stop) calculator computes Aperture opening area (in mm²) from focal length, f-number f/n, compare with f/n. Enter your values above and the exact formula is applied instantly; a worked example with real numbers is shown below.
Is the Aperture (f-stop) calculator free?
Yes. It is completely free, needs no signup, runs entirely in your browser, and sends no data to any server.
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