Calculate field of view

Calculate horizontal, vertical, and diagonal angle of view from focal length and sensor format.

freeworks offlinenothing uploaded
ToolField of View Calculator
Input
Output
—
Put this on your own site

The frame below runs the same code as this page, in the reader's own browser. Nothing is sent to us, and nothing is sent to you.

Pick a dark background and the text and panels follow it, so the frame stays readable on a dark page.

Preview

How it works

Angle of view is 2·atan(sensor dimension ÷ (2·focal length)) for each sensor dimension. A diagonal crop comparison divides full-frame diagonal by the selected sensor diagonal.

  • Stored sensor dimensions represent common formats.
  • The model is rectilinear and excludes fisheye distortion.

Worked example

50mm on full frame
The classic "standard" lens
Input
											50
Output
												Horizontal angle deg: 39.6
Vertical angle deg: 27
Diagonal angle deg: 46.8
Crop factor: 1

When to use this

Photographers compare lenses, virtual cameras choose framing, and cinematography lessons relate sensor size to angle.

Edge cases

  • Shorter focal length widens angle nonlinearly.
  • Fisheye lenses do not follow this rectilinear model.
  • Crop factor changes framing comparison, not physical focal length.