Aspect Ratio Explained: Why Photos Get Squashed or Cropped

The aspect ratio is the relationship between a photo's width and height. It's the reason images sometimes look stretched, or get cropped when you upload them.

What it means

An aspect ratio of 4:3 means for every 4 units of width there are 3 units of height. A 4000 × 3000 photo is 4:3, and so is 800 × 600.

Common ratios

Ratio	Shape	Typical use
1:1	square	profile pictures, some social posts
4:3	slightly wide	many phone and compact-camera photos
3:2	wider	many DSLR photos, 6 × 4 in prints
16:9	widescreen	video, thumbnails, presentation slides
4:5	slightly tall	portrait social posts
9:16	tall	phone stories and short videos

Why photos get squashed

If you force a photo into different dimensions without keeping the ratio, it stretches or squeezes. For example, changing 4000 × 3000 into 1000 × 1000 flattens the picture into a square. People look wider or thinner.

Two safe ways to change shape

1. Keep the ratio locked. Change only one dimension and let the other follow: 4000 × 3000 becomes 1000 × 750.
2. Crop to the new ratio. Remove parts of the picture instead of distorting it.

Doing the sum

To find a missing dimension, use: new height = new width × (old height ÷ old width).

Example: resizing a 4000 × 3000 photo to 1200 wide gives 1200 × (3000 ÷ 4000) = 900 high.

When a site demands a fixed size

If a form wants exactly 600 × 800 and your photo is a different shape, crop first to the right ratio, then resize. That avoids distortion.

Planning your crop

• Leave space around the subject if the platform trims edges.
• Keep faces away from the edges.
• Crop before resizing, so you keep as much quality as possible.

In a resizing app

A tool that lets you crop before or after resizing gives you both options, and lets you hit an exact size without a stretched result.

Try Image Compress & Resize Tool →