Gaming Calculators
Game FOV converter.
Games quote field of view as horizontal or vertical, and the two depend on the screen shape. Enter your FOV, say which kind it is, and the aspect ratio to get both values, plus the horizontal FOV on another aspect ratio if the vertical view stays fixed (Hor+). Runs in your browser; nothing is sent or stored.
Inputs
Result
Fill the form and press Calculate.
Worked example
A game set to 90 degrees horizontal FOV on a 16:9 screen has a vertical FOV of 2 x atan(tan(45 degrees) x 9 / 16) = 58.7 degrees. A game that fixes the vertical FOV at 58.7 degrees shows 73.7 degrees horizontal on a 4:3 screen. In the other direction, a vertical FOV of 90 degrees on 16:9 is 121.3 degrees horizontal.
How it works
For width w and height h: V = 2 arctan( tan(H / 2) x h / w ) and H = 2 arctan( tan(V / 2) x w / h ). These are the formulas given in the Field of view in video games - Wikipedia article, which also explains that Hor+ scaling, the most common method in modern games, keeps the vertical FOV fixed and widens the horizontal FOV on wider screens. The comparison line above assumes Hor+; games with Vert- scaling or a fixed horizontal FOV behave differently.
The tangent form matters: FOV does not scale in proportion to the aspect ratio, so you cannot multiply a horizontal FOV by 9 / 16 to get the vertical one.
Sources: Field of view in video games - Wikipedia. Each opened 2026-10-08.
Planning guide only, not professional advice. Figures are estimates from the inputs you enter.
FAQ
How do I convert horizontal FOV to vertical FOV?
Use V = 2 x arctan( tan(H / 2) x height / width ). For 90 degrees horizontal on 16:9 this gives about 58.7 degrees vertical.
How do I convert vertical FOV to horizontal FOV?
Use H = 2 x arctan( tan(V / 2) x width / height ). For 90 degrees vertical on 16:9 this gives about 121.3 degrees horizontal.
What is Hor+ scaling?
Hor+ keeps the vertical FOV fixed and expands the horizontal FOV on wider aspect ratios, so ultrawide players see more to the sides. It is the most common method in modern games.
Why is my FOV different in two games?
One may use horizontal and the other vertical FOV, and the aspect ratio changes the numbers. Convert both to the same type and aspect ratio before comparing.
Is a higher FOV always better?
A wider FOV shows more of the scene but makes objects in the centre smaller and can distort the edges, so it is a preference trade-off.