CalculatorCast

Field of View Calculator

Calculate horizontal, vertical, and diagonal angle of view for a lens/sensor.

Introduction

Field of View Calculator — Calculate horizontal, vertical, and diagonal angle of view for a lens/sensor. Enter Sensor Width, Sensor Height, Focal Length to get an instant, accurate result.

Formula

FOV = 2·atan(dimension / (2·f)), where f is focal length and dimension is the sensor width, height, or diagonal (all in the same units, converted to degrees).

Step-by-step

  1. Enter the Sensor Width.
  2. Enter the Sensor Height.
  3. Enter the Focal Length.
  4. Click Calculate to see your result instantly.

Real-world example

Example: With Sensor Width = 36 mm, Sensor Height = 24 mm, Focal Length = 50 mm, the Field of View Calculator gives Horizontal Fov Deg: 39.5978, Vertical Fov Deg: 26.9915, Diagonal Fov Deg: 46.793.

Frequently Asked Questions

Why is horizontal FOV different from vertical FOV?
Because the sensor is rectangular, not square — the wider dimension (width) produces a larger horizontal angle of view than the shorter dimension (height) at the same focal length.
Does a shorter focal length always mean a wider field of view?
Yes, for a fixed sensor size — the atan relationship means field of view increases as focal length decreases, which is why wide-angle lenses have short focal lengths.
What inputs does the Field of View Calculator need?
You'll need to provide: Sensor Width, Sensor Height, Focal Length. All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.
How accurate is the Field of View Calculator?
The Field of View Calculator applies the formula exactly as calculated — FOV = 2·atan(dimension / (2·f)), where f is focal length and dimension is the sensor width, height, or diagonal (all in the same units, converted to degrees). — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.
Is the Field of View Calculator free to use?
Yes, the Field of View Calculator is completely free, requires no signup, and runs instantly in your browser.

About the Field of View Calculator

The Field of View Calculator uses a real, verifiable formula — FOV = 2·atan(dimension / (2·f)), where f is focal length and dimension is the sensor width, height, or diagonal (all in the same units, converted to degrees). — so results are accurate every time, not an approximation.