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Image Aspect Ratio Calculator

Image

Reduce image width and height to an aspect ratio, compare common presets or read dimensions from a local image.

0
0
Dimensions
Common presets
Result
Simplified ratio
16:9

16:9 Widescreen · 1.7778 decimal

Pixels
1920 × 1080

Aspect ratio calculator that reduces a width and height to a ratio such as 16:9, with its decimal value. Type the pixel size or read it from a local image, and the nearest common preset is named when it matches within 2%.

See more about the Image Aspect Ratio Calculator

Examples

HD frame

1280 × 720 → 16:9 (1.7778)

Width and height are divided by their greatest common divisor, 80 here. A preset label appears when the ratio is within 2% of it.

Portrait crop

1080 × 1350 → 4:5 (0.8)

Click a preset to set the height from the current width. 4:3 on a 1920 px width gives 1440 px.

Key features

  • Simplified width:height ratio
  • Common preset buttons
  • Read dimensions from a local image
  • Decimal and pixel size

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Quick answers for Image Aspect Ratio Calculator

How is the ratio simplified?
Width and height are divided by their greatest common divisor, so 1280 by 720 becomes 16:9. The decimal is width divided by height, shown to four places.
Is my image uploaded?
No. Read from image uses the file pixel size in your browser, and the tool makes no network request for it.
Why does 1366 by 768 show 16:9?
1366 by 768 simplifies to 683:384, which is within 2% of 16:9, so it is labeled 16:9 Widescreen.
Can I type a custom ratio like 2.35:1?
No. You enter a width and height in pixels, and the ratio is worked out from them.