Focal Length Calculator

Convert focal lengths across sensor sizes and calculate field of view angles.

35mm Equivalent Focal Length
Horizontal FoV
Vertical FoV
Diagonal FoV
Crop Factor

Equivalent on Other Formats

Lens Category

Understanding Focal Length Equivalence

Crop factor multiplies the focal length to give the 35mm equivalent, which tells you the field of view compared to a full-frame camera.

Example: A 35mm lens on an APS-C (1.5x) camera gives the same field of view as a 52.5mm lens on full frame.

Related Calculators

Depth of Field

DoF from aperture and focal length.

Camera Sensor

Sensor sizes and crop factors.

Exposure

Exposure triangle calculations.

Lens Equation

Thin lens formula.

Aspect Ratio

Image dimensions and ratios.

Screen Size

Display size calculations.