Field of View Converter
Works out what a field of view means on another screen shape.
Horizontal FOV on the new aspect
— °
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Vertical FOV, kept the same — °
Horizontal FOV on the current aspect — °
Reading this —
The formula
vertical = 2 × atan(tan(horizontal ÷ 2) × height ÷ width) horizontal = 2 × atan(tan(vertical ÷ 2) × width ÷ height)
It is the tangent of the half-angle that scales with the screen, so an angle cannot just be multiplied by the ratio.
What to watch out for
Check what your game’s slider measures: some show horizontal FOV, some vertical, and some horizontal at a fixed reference aspect.
Frequently Asked Questions
What is 90° at 4:3 on a 16:9 screen?
106.26° horizontal, with the vertical held at 73.74°.
Why not just scale 90 by 16:9 over 4:3?
That gives 120°, which is wrong. The answer is 106.26°, because the tangent scales rather than the angle.