How is field of view calculated?

Field of view (FOV) is calculated using the formula: FOV = 2 × arctan(sensor dimension ÷ (2 × focal length)). The sensor dimension used determines whether you get horizontal, vertical or diagonal FOV. This assumes a rectilinear (non-fisheye) lens.

What affects field of view?

Two factors: focal length and sensor size. Shorter focal lengths give wider FOV. Larger sensors give wider FOV at the same focal length. A 50mm lens gives 39.6° horizontal FOV on full frame, but only 26.4° on an APS-C Nikon/Sony sensor (23.5 × 15.6 mm, a 1.53× crop) — about 27.0° on a nominal 24 × 16 mm 1.5× sensor.

What is the coverage area at a given distance?

The coverage area is the physical width and height of the scene captured at a given distance. At 10m with a 50mm full-frame lens, you capture approximately 7.2m × 4.8m of the scene (width = 36 × 10 ÷ 50 = 7.2m, height = 24 × 10 ÷ 50 = 4.8m). This is useful for planning group photos, architecture and event coverage.

What focal length gives a natural perspective?

The human eye has roughly 40-60° horizontal FOV for the central field of attention. A 43mm lens on full frame matches the sensor diagonal and gives about 53° diagonal FOV — considered the natural perspective. The classic 50mm lens is close at 46.8° diagonal.

Field of View Calculator — Horizontal, Vertical & Diagonal FOV

Calculate the horizontal, vertical and diagonal field of view for any lens and sensor combination.

Focal Length

Actual lens focal length in mm (e.g. 35, 50, 85). Use the true focal length, not the full-frame-equivalent.

Sensor SizePick your camera's sensor format, or choose Custom to enter exact width × height in mm.

Subject Distance

Distance from camera to subject in metres — used to work out the scene coverage (width × height) at that range.

How We Calculate This

Field of view is calculated from the sensor dimensions and focal length:

FOV Formula

FOV = 2 × arctan(dimension ÷ (2 × focal length))

Use sensor width for horizontal FOV, height for vertical, and the sensor diagonal for diagonal FOV. The formula assumes a rectilinear (non-fisheye) lens.

Scene Coverage

Coverage = 2 × distance × tan(FOV ÷ 2)

For a 50mm lens on full frame at 10m this gives 7.2m × 4.8m of horizontal × vertical coverage.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard optical and photographic formulas. Results may vary with specific equipment.