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DESIGN UTILITIES

Aspect Ratio Calculator

Enter original width and height to get the simplified aspect ratio, decimal ratio, and matching width or height for a target size.

Tool statusRuns in your browser
Preview

Inputs

Results

Aspect ratio
16:9
Decimal
1.7778
Width from height
1280
Height from width
720

Keep the same proportion when resizing images, videos, or layouts.

How it works

  1. Enter your input

    Fill in the values, paste your text, or upload the file this tool works with.

  2. See results instantly

    Most tools update live as you type; a few use a single button. Either way, the result appears right on this page.

  3. Use your results

    Copy, download, or share what the tool produces — you're always in control of the output.

Privacy and processing — Runs locally in your browser. This tool does not upload your input.

What is Aspect Ratio Calculator?

Find a simplified width-to-height ratio and calculate matching dimensions for images, videos, and layouts.

UNDERSTAND THE TOOL

How to calculate aspect ratio

How to use it

  • Enter the original width and height.
  • Enter a target width to calculate the matching height.
  • Enter a target height to calculate the matching width.

Why aspect ratio matters

Aspect ratio keeps visual content from stretching. A 1920 by 1080 image simplifies to 16:9, so any resized version should keep that same relationship.

Common uses

  • Preparing images for social posts, thumbnails, or banners.
  • Resizing videos without distortion.
  • Checking layout proportions before exporting assets.

Worked example

Ratio
width : height reduced by gcd
Width from height
target_height * width / height

1920 x 1080

The simplified ratio is 16:9; a 720 px height maps to 1280 px width.

Dimension notes

The calculator preserves the ratio between width and height. Round final dimensions according to the export preset, layout grid, or platform requirement you are targeting.

Frequently Asked Questions

What does 16:9 mean?

It means the width has 16 parts for every 9 parts of height.

Does this resize an image file?

No. It calculates proportional dimensions. Use the Image Resizer when you need to process an actual file.

Can I use decimals?

The interface is intended for pixel dimensions, so whole numbers are the most useful input.

Can I use decimal dimensions?

Yes. Decimal dimensions are scaled before reducing the ratio, up to six decimal places.

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