What are black bars in games?

Black bars appear when the game renders at a different aspect ratio than your monitor. Pillarbox bars appear on the left and right when the game is narrower than the screen (e.g. 4:3 on a 16:9 monitor). Letterbox bars appear on the top and bottom when the game is wider than the screen (e.g. 21:9 content on a 16:9 monitor).

Why do competitive players use 4:3 on a 16:9 monitor?

Many CS2 and Valorant players use 4:3 because it was the native ratio of older games like CS 1.6. Player models appear slightly wider and can be easier to click. Some players also find reduced peripheral distractions help focus. The trade-off is losing horizontal screen area, shown as pillarbox bars unless stretched mode is used.

What is stretched vs. black bar mode?

In black bar mode, the game renders at the correct aspect ratio and bars fill unused screen space. In stretched mode, the GPU scales the image to fill the entire screen, distorting models and geometry. This calculator computes the black bar pixel dimensions for non-stretched setups.

How does aspect ratio affect FOV?

Most modern games use Hor+ FOV scaling. Widening your aspect ratio (e.g. 16:9 to 21:9) keeps vertical FOV constant and increases horizontal FOV — you see more of the scene. Narrowing (e.g. to 4:3) reduces horizontal FOV. This calculator shows the exact change so you can decide whether to adjust your in-game FOV setting.

What resolution should I use for a specific aspect ratio?

Set width divided by height equal to the target ratio. For 4:3 on a 1080p display, use 1440x1080 or 1280x960. This calculator automatically computes the correct dimensions.

Does my GPU need to support the target resolution?

Yes. The target resolution must be supported by your GPU driver and the game. Most modern GPUs support custom resolutions through their control panel. Some games restrict available resolutions — pick the closest one the game supports.

Aspect Ratio Game Calculator

Name: Aspect Ratio Game Calculator
Availability: InStock
Author: Nham Vu

Calculate game resolution, FOV adjustments, and black bar sizes when switching between aspect ratios like 16:9, 4:3, and 21:9.

Source Aspect Ratio

Ratio: 1.7778

Target Aspect Ratio

Ratio: 1.3333

Monitor Resolution

1920 x 1080

Source H-FOV (optional)

Horizontal FOV at source ratio. Leave at 90 if unsure. Used to calculate target FOV.

Output Resolution

—

at target ratio

Black Bars

—

pixels per side

Target H-FOV

—

degrees

FOV Change

—

vs. source

Screen Layout Preview

Configure ratios above to see layout

All Common Aspect Ratios on Your Monitor

Hor+ scaling, source V-FOV held constant

Aspect Ratio	Resolution	Black Bars	H-FOV	FOV Change
Configure inputs above to see results.

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Summary

Calculate game resolution, FOV adjustments, and black bar sizes when switching between aspect ratios like 16:9, 4:3, and 21:9.

How it works

Select your source aspect ratio (the ratio your game is currently set to).
Select your target aspect ratio (the ratio you want to switch to).
Enter your monitor resolution width and height.
The calculator shows the output resolution scaled to the target ratio.
Black bar widths (letterbox or pillarbox) are computed automatically.
FOV adjustment shows how much wider or narrower your view becomes.

Use cases

Find the correct resolution when forcing 4:3 on a 16:9 monitor for competitive play.
Calculate pillarbox bar widths when running an old game at 4:3 on a widescreen display.
Determine letterbox bar heights when playing a 21:9 game on a 16:9 screen.
Preview how much FOV you gain or lose when switching from 16:9 to 21:9 ultrawide.
Compare multiple target aspect ratios side by side before committing to a setup change.
Calculate the exact pixel dimensions for a custom in-game resolution.
Understand black bar sizes before adjusting in-game or GPU scaling settings.
Check whether a 32:9 ultrawide gives a meaningful FOV advantage over 21:9.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu