Camera lens focal length calculator
Pick the right lens before you buy. Enter how far away the subject is and how wide the scene needs to be — we'll show the focal length you need on every common sensor size.
- Required focal length
- 14.0 mm
- Horizontal FOV
- 23°
Same shot on other sensors:
- 1/3" (4.8 mm wide)12.0 mm
- 1/2.8" (5.6 mm wide)14.0 mm
- 1/2.5" (5.76 mm wide)14.4 mm
- 1/1.8" (7.2 mm wide)18.0 mm
Sensor size changes everything
A 4 mm lens on a 1/1.8" sensor is much wider than a 4 mm lens on a 1/3" sensor. Always match the lens spec to the actual sensor in the camera you're quoting.
Want pixel density too?
Use the FOV & DORI calculator to translate focal length into Detect / Observe / Recognize / Identify ranges per the EN 62676-4 standard.
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