Field of View Calculator
Calculate the horizontal, vertical, and diagonal angle of view from focal length and sensor dimensions, plus how much of a scene you'll capture at a distance.
Full-frame is 36 × 24 mm, APS-C is roughly 23.6 × 15.6 mm, and Micro Four Thirds is 17.3 × 13 mm. Subject distance is optional and just estimates how much scene you'll capture.
How it works
Angle of view is how wide a slice of the world your lens takes in, measured in degrees. It comes straight from geometry: twice the arctangent of the sensor dimension divided by twice the focal length.
Because a sensor is wider than it is tall, you get three numbers — horizontal, vertical, and the diagonal that lens makers usually quote. A short focal length spreads the angle wide; a long one narrows it to a tight slice.
Enter an optional subject distance and the tool also estimates how many metres of scene fit in the frame there, which is the practical answer when you're deciding whether everyone fits in the group photo.
Frequently asked questions
What sensor dimensions should I use?
Full-frame is 36 by 24 mm, typical APS-C is about 23.6 by 15.6 mm, and Micro Four Thirds is 17.3 by 13 mm. Your camera's spec sheet lists the exact figures if you want to be precise.
Why is the diagonal angle the biggest?
The diagonal is the longest measurement across the sensor, so it always spans a wider angle than the horizontal or vertical edges. That's the figure most lens marketing quotes.
Does focal length alone decide the field of view?
No — sensor size matters just as much. The same 50 mm lens looks like a normal view on full frame but noticeably tighter on a smaller sensor, because the sensor crops into the image circle.