Crop to Aspect Ratio Calculator
Enter the size of your image and the ratio you need, such as 16:9, 1:1, 4:5 or 1.91:1, and see the largest crop of that shape that fits inside it. The result shows the crop size, the pixel where it starts, how many pixels are cut from each side, and how much of the picture you keep. Two sliders move the crop toward the left, right, top or bottom, a drawing shows the crop on the image, and a table lists the same image cropped to every common ratio. It also writes the ffmpeg crop filter, the ImageMagick option and the CSS object-position rule. Everything runs in your browser.
The same image cropped to each common ratio
| Ratio | Largest crop | Kept |
|---|---|---|
| 1:1 | 3000 x 3000 | 75% |
| 4:5 | 2400 x 3000 | 60% |
| 3:4 | 2250 x 3000 | 56.3% |
| 2:3 | 2000 x 3000 | 50% |
| 9:16 | 1688 x 3000 | 42.2% |
| 5:4 | 3750 x 3000 | 93.8% |
| 4:3 | 4000 x 3000 | 100% |
| 3:2 | 4000 x 2667 | 88.9% |
| 16:10 | 4000 x 2500 | 83.3% |
| 16:9 | 4000 x 2250 | 75% |
| 1.91:1 | 4000 x 2094 | 69.8% |
| 2:1 | 4000 x 2000 | 66.7% |
The largest crop of a ratio keeps one side of the picture whole and trims the other. If the picture is wider than the target ratio, the height stays and the width shrinks to height times the ratio; if it is taller, the width stays and the height shrinks. The position sliders decide how the leftover is split: 50% cuts equally from both sides, 0% keeps the left or top edge. Sizes are whole pixels, so a ratio such as 16:9 can be off by a fraction of a pixel unless you ask for an exact crop. Everything runs in your browser and no image is uploaded.
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Format ConversionAbout the Crop to Aspect Ratio Calculator
The largest crop of a ratio keeps one side of the picture whole and trims the other. If the picture is wider than the target ratio the height stays and the width becomes the height times the ratio; if it is taller the width stays and the height becomes the width divided by the ratio. For a 4000 x 3000 photo, a 16:9 crop is 4000 x 2250 and starts 375 pixels from the top, so 375 pixels go from the top and 375 from the bottom, and 75% of the area is kept. A 1:1 crop is 3000 x 3000 starting 500 pixels from the left, and a 4:5 crop is 2400 x 3000 keeping 60%. A 1.91:1 crop is 4000 x 2094 and keeps 69.8%. The same idea cuts a 1920 x 1080 frame to a 608 x 1080 vertical 9:16 strip that starts 656 pixels from the left and keeps 31.7%. The position sliders decide how the leftover is shared: 50% cuts equally, 0% keeps the left or top edge. Sizes are whole pixels, so a ratio such as 16:9 can be a fraction of a pixel off, and the exact option picks the largest size that has the ratio with no rounding. No image is uploaded.
How do I crop an image to a 16:9 ratio?▾
Keep the width and set the height to the width times 9 divided by 16. A 4000 x 3000 photo becomes 4000 x 2250, which removes 750 pixels of height, split between the top and the bottom.
How much of my photo will be lost?▾
The tool shows the kept share of the area. For a 4000 x 3000 photo, 16:9 and 1:1 keep 75%, 4:5 keeps 60% and 4:3 keeps all of it.
Can I move the crop away from the center?▾
Yes. The position sliders run from 0% to 100%. 50% is the center, 0% keeps the left or top edge, and 100% keeps the right or bottom edge.
Why is the ratio a little off?▾
Pixels are whole numbers, so a size such as 1365 x 768 is not exactly 16:9. Tick the exact option to get the largest size where the ratio is exact, such as 1360 x 765.
Is my image uploaded?▾
No. You only type the size of the image, and the calculation runs in your browser.