What is the 4:3 aspect ratio?

It means for every 4 units of width there are 3 units of height. Dividing 4 by 3 gives the ratio ≈ 1.3333. This was the standard for analog television, early computer monitors, and many digital cameras.

How do I calculate the height from a given width?

Multiply the width by 3 and then divide by 4. For example, a width of 1024 px gives a height of 1024 × 3 / 4 = 768 px.

How do I calculate the width from a given height?

Multiply the height by 4 and then divide by 3. For example, a height of 600 px gives a width of 600 × 4 / 3 = 800 px.

What are common 4:3 resolutions?

640×480 (VGA), 800×600 (SVGA), 1024×768 (XGA), and 1600×1200 (UXGA) are the most common 4:3 resolutions.

Does this tool work in units other than pixels?

Yes. The 4:3 ratio is dimensionless, so the same math applies to centimeters, inches, millimeters, or any other unit. Just treat the numbers as your chosen unit.

Why was 4:3 the original TV and monitor standard?

The 4:3 ratio was inherited from early film formats and became the global standard for analog broadcast television. It remained dominant for computer monitors until widescreen 16:9 displays took over in the late 2000s.

4:3 Aspect Ratio Calculator

Enter a width or height and instantly get the matching 4:3 dimension.

Enter a Dimension

Width

Height (computed)

Common Presets

Result

Enter a dimension to see the result.

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Summary

The 4:3 aspect ratio is the classic standard for older television sets, traditional computer monitors, and VGA displays. This calculator lets you enter either a width or a height and instantly computes the missing dimension so every resolution stays perfectly proportional. Results are shown in pixels, but the math works for any unit.

How it works

Choose whether you know the width or the height.
Type the known dimension into the input field.
The calculator instantly computes the missing dimension using the 4:3 ratio.
Common presets (VGA, SVGA, XGA, UXGA) are provided for one-click filling.
Copy either dimension to your clipboard with one click.

Use cases

Calculate the correct height for a 1024 px wide presentation slide.
Find the width for an 800 px tall legacy monitor layout.
Verify that a scanned document or photo is true 4:3.
Size PowerPoint or Keynote slides for older projectors.
Ensure retro-style game assets maintain correct fullscreen proportions.
Set up video export settings for standard-definition content.
Design iframes or embedded content targeting classic display ratios.
Convert non-standard dimensions to the nearest 4:3 equivalent.

Frequently Asked Questions

Last updated: 2026-05-23 · Reviewed by Nham Vu