How to Resize an Image Without Stretching It
A picture looks stretched or squashed when its width and height are changed by different amounts. To resize an image without distortion, change only one side and let the other follow at the same proportion. In Image Compress, you do that by typing a number in Max width: the height is scaled to match automatically, so nothing gets stretched.
If you need a different shape altogether, such as a square from a landscape photo, resizing alone can't get you there without distortion. You crop first, then resize. Both cases are covered below.
What aspect ratio means
An image's aspect ratio is the relationship between its width and its height. A photo that's 1920 pixels wide and 1080 pixels tall has a ratio of 16:9, the usual widescreen shape. A 1080 × 1080 image is 1:1, a square. Many phone photos are 4:3, for example 4000 × 3000 pixels.
As long as the ratio stays the same, the picture looks right at any size. A 4000 × 3000 photo shrunk to 1200 × 900 is still 4:3, just smaller. Distortion happens when the ratio changes: squeeze that same photo into 1200 × 1200 without cropping and everything in it gets pulled taller and thinner. Faces look long, circles turn into ovals and text leans out of shape.
How stretching usually happens
- Typing both width and height in an editor that doesn't lock them together, with numbers that don't match the original shape.
- Dragging a corner or side handle freely in a document, slide or design app, instead of a locked corner drag.
- A website or app forcing a box size, such as a 400 × 400 profile slot, on a photo that isn't square.
The fix in each case is the same idea: keep the proportions locked, and if the shape really has to change, cut away part of the picture rather than squashing it.
Resize proportionally with Image Compress
Image Compress is built to shrink photos for email, upload forms and websites, and its Max width setting always keeps the proportions.
- Open Image Compress and click the upload area to pick your image. PNG, JPG and WebP work, as does any other image type your browser can open.
- Type the width you want, in pixels, in Max width. The height is calculated for you. Leave it at 0 to keep the original size.
- Check the final dimensions in the four boxes under the controls. They show original size, compressed size, percentage saved and final dimensions, and the preview updates a moment after each change.
- Choose an output format. JPEG is the safe choice for photos and is accepted almost everywhere. PNG is lossless, meaning it keeps every pixel exactly, which suits screenshots, logos and graphics with sharp text. WebP usually gives a smaller file and keeps transparency.
- Leave Quality at 80% to start. It only affects JPEG and WebP.
- Click Download. The file is saved with -compressed added to its original name.
Working out the new height
You don't need to calculate it, because the tool shows the final dimensions. But it helps to know what to expect. The new height is the original height multiplied by the new width, divided by the original width.
| Original | Max width | Result |
|---|
| 4000 × 3000 (4:3) | 1200 | 1200 × 900 |
| 1920 × 1080 (16:9) | 1280 | 1280 × 720 |
| 3000 × 4000 (3:4, portrait) | 900 | 900 × 1200 |
For portrait photos, remember that Max width controls the narrow side. If you need a tall picture to be no more than 1200 pixels high, set the width to about three-quarters of that for a 3:4 photo.
What it won't do
Max width can only make images smaller. It won't enlarge a small picture. That's a sensible limit anyway: making a small image bigger can't add detail that was never captured, so it tends to look soft or blurry. If you need a larger image, go back to the original photo if you have it.
When you need a different shape: crop, then resize
Say a shop listing wants a square image and your product photo is a wide 16:9 shot. If you force it into a square, the product gets squashed. Instead:
- Open Image Crop and lock the crop to the shape you need. It works freehand or locked to common shapes such as 1:1 or 16:9.
- Position the crop over the part of the photo you want to keep and save it.
- Bring the cropped image back to Image Compress and set the max width to the size the site asks for. Because the crop is already the right shape, the result comes out at the right dimensions without any stretching.
For a round profile picture, Circle Image Crop turns a photo into a circle with a see-through background, so you don't need to squeeze it into shape.
If you'd rather keep the whole picture and can't crop, the other honest option is to add empty space (padding) around it to reach the target shape. That isn't something our tools do, but most photo editors and design apps can place an image on a larger blank canvas.
Resizing on your phone or in other apps
Your phone's built-in photo editor can often crop to a fixed ratio, and that's a perfectly good option for a quick square crop. In document and slide apps, dragging a corner handle (rather than a side handle) usually keeps the proportions, and many apps have a "lock aspect ratio" option in the picture settings. If an image already looks stretched in a document, resetting its size in the app's picture settings is usually quicker than starting over.
Tips for a sharp result
- Always start from your original file. Compressing the same JPEG again and again loses a little more detail each time.
- Pick the width the image will actually be shown at. Most web pages display images under 1600 pixels wide, so 1200 to 1600 is a good range for blog posts, shops and listing sites.
- If the Saved box turns red, the new file is bigger than the original. Lower the quality or switch format, for example from PNG to JPEG for a photo.
- Very large images can be slow on older phones, because all the work happens on your device. Your image is never sent to our server.
If the site gives you exact dimensions in a different shape from your photo, crop to that ratio first. If it only gives a maximum width, Max width on its own is all you need.
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