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Upload a landscape photo as an Instagram Story and you get a thin strip in the middle of the screen. Use a phone video on YouTube and black bars appear on both sides. These problems all come down to aspect ratio.
What is aspect ratio?
Aspect ratio describes an image’s shape — its width compared with its height — written as width : height.
- 1:1 — width equals height (square)
- 4:5 — slightly taller than wide
- 16:9 — much wider than tall (widescreen)
- 9:16 — much taller than wide (vertical phone screen)
Ratio is about shape, not size: a 400 × 300 image and a 4000 × 3000 image are both 4:3.
Common ratios and where they’re used
| Ratio | Shape | Where you’ll see it |
|---|---|---|
| 1:1 | Square | Profile photos, Instagram square posts, product photos |
| 4:5 | Tall portrait | Instagram portrait posts (largest in the feed) |
| 3:2 | Classic photo | Many cameras, standard 6 × 4 inch prints |
| 4:3 | Standard | Phone camera photos, older screens, iPads |
| 16:9 | Widescreen | YouTube, TVs, laptops, presentations |
| 9:16 | Vertical full screen | Reels, Stories, Shorts, WhatsApp Status |
| 7:9 (35 × 45 mm) | Passport photo | Passport and visa photos in many countries |
Working out a ratio from pixels
Divide width and height by their greatest common divisor:
1920 × 1080: both divide by 120 → 16 × 9.
1080 × 1350: both divide by 270 → 4 × 5.
1080 × 1920: both divide by 120 → 9 × 16.
Never stretch — crop instead
Forcing a photo into a different shape by stretching makes faces look wide or thin. To change ratio properly you either:
- Crop — cut away part of the image so the remaining area has the new shape, or
- Pad — add space (a blurred copy, a solid colour, or bars) around the whole image.
Cropping tips
- Keep the subject’s eyes about one-third from the top for portraits.
- Leave breathing room — don’t crop right at the chin or the top of the head.
- Watch the edges — avoid cutting through hands, feet or important text.
- Start from a high-resolution photo so the cropped result still has enough pixels.
Going from a landscape 16:9 photo to a vertical 9:16 crop keeps only about a third of the width. If the subject isn't central, it may be better to use a blurred background instead of cropping.
Crop to any ratio
Our Crop Image tool has presets for square, 4:5, 16:9, 9:16, 4:3 and passport size. Drag to select the area, move it to frame your subject, and download as JPG, PNG or WebP — all in your browser.
Free toolTry the Crop ImageCut out the part of a photo you want, freely or in a fixed shape.Frequently asked questions
Is 1080 × 1080 the same as 1:1?
Yes. Any image with equal width and height is 1:1, whether it's 500 × 500 or 1080 × 1080.
How do I calculate a ratio from pixels?
Divide both numbers by their greatest common divisor. 1920 × 1080 ÷ 120 = 16 × 9, so it's 16:9.
Can I change ratio without cropping?
Only by adding space around the image (letterboxing, a blurred background or a solid colour). Otherwise you have to crop.
Written by the Toolsopedia team. Spotted an error? Tell us and we’ll fix it.