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Gaming Runs in browser Updated 30 Mar 2026

FOV Calculator

Convert field of view between horizontal, vertical, and diagonal for any aspect ratio. Game presets for CS2, Valorant, Apex, Overwatch 2, and more with a live FOV diagram.

Calculated FOV values

Horizontal FOV

90.00°

Vertical FOV

58.72°

Diagonal FOV

97.85°

FOV visualization (HFOV)

90.00°

Recommended FOV for 16:9

90° – 110°

The standard competitive range. Lower values help with long-range aim, higher values improve peripheral awareness.

FOV conversion uses the tangent-based formula that accounts for aspect ratio geometry. Game presets use HFOV values. Some games display VFOV in their settings — check your title's documentation if results seem off.
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How to use FOV Calculator

  1. Enter your FOV value

    Type your current horizontal or vertical field of view value, or click a game preset to auto-fill the default FOV for CS2, Valorant, Apex Legends, Overwatch 2, or Fortnite.

  2. Select your aspect ratio

    Choose from 16:9, 21:9, 4:3, or 16:10 aspect ratio presets, or enter a custom width and height ratio to match your monitor exactly.

  3. Choose the input type

    Switch between HFOV input and VFOV input depending on which value your game exposes. CS2 uses HFOV; most Unreal Engine games like Apex Legends use VFOV.

  4. Read all three FOV values

    View your horizontal, vertical, and diagonal FOV simultaneously alongside a live visual diagram showing the angle and a recommended range for your aspect ratio.

FOV Calculator FAQ

What is the difference between horizontal and vertical FOV?
Horizontal FOV (HFOV) is the angle of your visible game world measured left to right. Vertical FOV (VFOV) measures top to bottom. Most games expose one value and calculate the other from your aspect ratio — CS2 uses HFOV while Apex Legends, Overwatch 2, and most Unreal Engine titles use VFOV.

Why does aspect ratio change my FOV?
A wider aspect ratio (like 21:9) shows more of the world horizontally for the same vertical FOV. The mathematical relationship between HFOV and VFOV depends entirely on the width-to-height ratio of your display — changing your aspect ratio changes both the feel and the correct converted value.

What FOV should I use for competitive FPS at 16:9?
Most competitive players on 16:9 monitors use an HFOV of 90–110 degrees (roughly 59–74 VFOV). Lower FOV makes distant targets appear larger and easier to aim at; higher FOV provides better peripheral awareness. The meta for CS2 is 90 HFOV; Valorant defaults to 103 HFOV.

Does a higher FOV reduce FPS?
Yes. A higher FOV causes the game to render more of the scene, increasing GPU and CPU load. The impact varies by game engine, but you may see a measurable FPS drop at very wide FOV values (120+ HFOV) compared to narrower settings.

What is diagonal FOV and when does it matter?
Diagonal FOV (DFOV) measures the field of view from one corner of the screen to the opposite corner. VR headsets and some niche games use DFOV as their primary specification. It is always larger than both HFOV and VFOV for the same scene.

What FOV should I use with a 21:9 ultrawide monitor?
With a 21:9 monitor you have much wider HFOV for the same VFOV. If you're used to 103 HFOV on 16:9 CS2, you'd need roughly 125 HFOV on 21:9 to get the same vertical perspective. Use this calculator to find the equivalent value.

Why does CS2 use HFOV while Valorant uses HFOV too?
Both CS2 (Source engine) and Valorant use horizontal FOV. However, Overwatch 2 and Apex Legends use vertical FOV. Entering '103' in CS2 gives you HFOV 103; entering '103' in Overwatch 2 gives you VFOV 103 — a very different result on 16:9. Always check which type your game uses.

What is the monitor distance coefficient for FOV conversion?
Monitor distance coefficient is a sensitivity conversion concept related to how much screen real-estate a target occupies as FOV changes. It's separate from raw FOV measurement. Use the sensitivity converter if you need to transfer your cm/360 between games at different FOV settings.

Background

Instantly convert between horizontal, vertical, and diagonal field of view for any aspect ratio with a real-time visual diagram that scales to your current angle. Enter your HFOV or VFOV value, pick your aspect ratio, and get all three FOV measurements immediately.

Choose from common aspect ratio presets (16:9, 21:9, 4:3, 16:10) or enter a custom width and height ratio to match your exact monitor. One-click game presets for CS2, Valorant, Overwatch 2, Apex Legends, and Fortnite let you jump straight to each title's default FOV setting. The tool also shows a recommended FOV range for your selected aspect ratio to help you balance peripheral awareness against target visibility.

Understanding which FOV type your game uses matters: CS2 uses HFOV (Source engine), while Overwatch 2 and Apex Legends use VFOV. Entering the same number produces very different views — this calculator converts between them. All calculations run entirely in your browser.

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