f-Number / Aperture calculator
Relationship between focal length, aperture diameter and f/#.
Category: Imaging
Formula: N = f / D
Inputs
| Input | Parameter | Unit | Default |
|---|---|---|---|
| Focal length | f | mm | 50 |
| Aperture | D | mm | 25 |
Result with the default inputs
- f-number: f/2
- Rel. aperture: 0.5
Open it with your own values: put each input in the address as a parameter, for example /calculators/f-number-aperture?f=50. A unit other than the listed one goes in <parameter>_unit.
Read more: Wikipedia: F-number