GCSAim Utility
FOV Converter
Keep the same field of view when you switch games or aspect ratio. Enter your FOV once and get the matching value everywhere else - the actual view stays identical.
- Horizontal FOV
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- Vertical FOV
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at the target aspect ratio
How FOV conversion works
A field-of-view value is just the angle the camera covers, but games measure it differently - some by the horizontal angle, some by the vertical angle, and each against a reference aspect ratio. This converter turns your value into the true vertical field of view, then re-derives the matching number for the target game and aspect ratio using exact frustum trigonometry, so the world looks exactly the same size on screen.
Horizontal vs vertical FOV
The Source engine family - Counter-Strike 2, CS:GO, Apex Legends - and Call of Duty measure FOV horizontally against a 4:3 base. Battlefield and some others use vertical FOV. If you are unsure which your game uses, pick the explicit "Horizontal" or "Vertical" option and your aspect ratio.
4:3, 16:9 and ultrawide
This tool uses Hor+ scaling, the competitive standard: when you go wider (16:9, 21:9, 32:9) the vertical view stays put and the horizontal view expands, so you see more at the sides without zooming. That is why a 90 horizontal FOV at 4:3 becomes about 106 at 16:9 - the same view, just wider.
Why match your FOV?
Your muscle memory learns how big targets look and how far they move per mouse count. Keeping the on-screen view identical across games means your aim transfers cleanly - the same reason you would match your sensitivity. Pair this with the sensitivity converter for a fully consistent setup.