FOV Calculator: convert field of view between axes and aspect ratio
Convert horizontal, vertical and diagonal FOV into each other, recalculate it on an aspect ratio change, and check the "4:3 stretched" case.
How we calculate
Everything rests on one trigonometric relation between FOV and aspect ratio: tan(H/2) = (w/h)·tan(V/2). Enter a known value on any of the three axes — horizontal, vertical, or diagonal — plus the screen aspect ratio, and the calculator derives the rest from that same formula; the diagonal is additionally derived via the Pythagorean theorem on the legs tan(H/2) and tan(V/2) — nobody publishes that step separately, it is our own direct geometric consequence of the same camera model.
Hor+ and Vert− are two ways to handle FOV on an aspect ratio change (say, going from 4:3 to 21:9). In Hor+ the vertical FOV stays fixed while the horizontal FOV grows with a wider screen — this is what most modern games do. In Vert− it is the opposite: the horizontal FOV stays fixed and the vertical FOV is trimmed to compensate for a wider screen. In the "4:3 stretched" case (a 4:3 render stretched without black bars onto a 16:9 display) the FOV in degrees does NOT change — stretching is a post-render pixel remap; what changes is only how much wider objects appear, and that is exactly the stretch factor the calculator shows, without inventing a made-up "effective FOV".
Honestly, about PUBG: the game has an FPP FOV slider, but we could not find official documentation of its exact range or of whether it drives the horizontal or the vertical axis. Channels checked: pubg.com and support.pubg.com (403s and empty search results), patch-note pages, PCGamingWiki (403), several third-party calculators and guides (which contradict each other — 70-80 vs. 90 as the minimum/default, with no official citation), and the Wayback Machine (unreachable from this tool). So no PUBG-specific numbers appear here — the converter above is fully generic and works with whatever value your own game displays.
Sources
checked 1 September 2026
Questions and answers
Why isn't there an exact PUBG FOV slider range here?
Because we could not find official documentation for that range: pubg.com and support.pubg.com return no numbers (403s and empty search results), PCGamingWiki returned 403, several third-party calculators and guides contradict each other (70-80 vs. 90 as minimum/default, with no official source), and the Wayback Machine is unreachable from this tool. We chose not to invent a number — the converter above works with whatever value you see in your own game.
What are Hor+ and Vert−?
Hor+ keeps the vertical FOV fixed and widens the horizontal FOV as the screen gets wider — this is what most modern games do. Vert− is the opposite: it keeps the horizontal FOV fixed and trims the vertical FOV as the screen gets wider.
Does stretching 4:3 onto a wide screen actually change FOV?
No. Stretching is a pixel remap that happens after rendering — it does not change the angle the camera captured. What changes is only how much wider objects appear on screen; that's exactly what the stretch factor in the block above shows.
How is "apparent target size" different from "cm/360"?
"cm/360" is about mouse sensitivity and the physical mouse-pad distance for a full character turn — it has nothing to do with FOV. Our metric is about how much bigger or smaller the same object looks on screen when only the FOV value changes.
Where does the FOV conversion formula come from?
The core equation tan(H/2) = (w/h)·tan(V/2) and the Hor+/Vert− definitions come from the Wikipedia article "Field of view in video games" (linked in sources below). The diagonal and the stretch factor are our own geometric derivation from that same camera model.
All PUBG: Battlegrounds guides
Unofficial tool. Not affiliated with KRAFTON, Inc.