FOV Calculator - Camera Field of View
Calculate a camera's horizontal, vertical, and diagonal field of view from sensor size and focal length.
Diagonal Field of View
46.8°
Horizontal FOV
39.6°
Vertical FOV
27.0°
How to Calculate Camera Field of View
A lens's angle of view depends on both the focal length and the size of the camera's sensor. Pick a common sensor preset (or enter a custom sensor size) and a focal length to get the horizontal, vertical, and diagonal field of view in degrees.
Example
A full-frame sensor (36mm × 24mm) with a 50mm lens gives a horizontal FOV of 2 × arctan(36 ÷ 100) ≈ 39.6°, a vertical FOV of 2 × arctan(24 ÷ 100) ≈ 27.0°, and a diagonal FOV (using the 43.3mm sensor diagonal) of about 46.8°.
Common Use Cases
- Choosing a lens focal length for landscape, portrait, or architectural photography.
- Comparing how the same focal length behaves on different sensor sizes.
- Planning a shot's framing before arriving on location.
FAQs
Why do APS-C cameras have a "crop factor"?
A smaller sensor captures a narrower slice of the same lens's image circle, producing a narrower field of view than a full-frame sensor at the same focal length — this narrowing is commonly expressed as a crop factor multiplier, typically around 1.5x to 1.6x for APS-C sensors.
Which FOV value matters most — horizontal, vertical, or diagonal?
Horizontal FOV is the most commonly cited figure for landscape-orientation shooting, vertical FOV matters more for portrait orientation, and diagonal FOV represents the sensor's true corner-to-corner angle of view, which is what lens focal length ratings are technically based on.
Does lens distortion affect the actual field of view?
This formula assumes an ideal rectilinear lens. Real lenses — especially wide-angle and fisheye designs — introduce some distortion, which can make the practically perceived field of view differ slightly from this idealized trigonometric calculation.