Aspect Ratio Calculator
Aspect ratio is the relationship between width and height. Use this calculator to calculate image and video dimensions.
I know the
Height · exact
1920 × 1080 px
Whole pixels — no rounding needed.
Precision detail
- Target ratio
- 16:9
- Exact height
- 1080/1 px
- Decimal
- 1080 px
- Rounded
- 1,080 px (half up)
Parentheses mark repeating digits; … marks a truncated decimal. Fractions are exact.
Drag the corner dot or use arrow keys. Near means a similar common ratio, not an exact match. Exact values are in precision detail.
How to use the aspect ratio calculator
“An aspect ratio is the proportional relationship between an element or viewport's width and height.”
Divide both dimensions by their greatest common divisor: 1920 × 1080 becomes 16:9. See MDN’s common aspect ratios for widescreen and cinema examples.
- 1Calculate size. Choose an image or video ratio, then enter the width or height you know. Decimals like 2.39:1 work.
- 2Calculate aspect ratio. Enter image or video dimensions in Aspect ratio, then use the result in Calculate size.
- 3Calculate scaled dimensions. In Resize, enter the original image dimensions and a target width or height.
- 4Copy. Copy the dimensions or ratio. Expand precision detail for exact values.
This calculator returns dimensions and aspect ratios; it does not resize or crop files.
Image and video calculator examples
- Image 6000 × 40003:2
- Video 1920 × 108016:9
- Vertical video 1080 × 19209:16
- 16:9 at 1001 wide1001 × 563 px (rounded)
- 3440 × 1440 ultrawide43:18 (not exactly 21:9)
- 2560 × 108064:27