How to Resize an Image Without Losing Quality (Any Device)
Published 2026-10-27
Websites, forms and social networks all want images at particular sizes. Resizing is simple once you know two rules: keep the proportions locked, and make images smaller, not bigger. Here’s how to do it on every device.
The quickest way on any device
- Open the Image Resizer and choose your image.
- Type the new width; the height adjusts automatically.
- If there’s a file size limit, type it in KB.
- Download the result.
On Windows
- Photos app: open the image, open the “…” menu and choose Resize image, then pick a preset or enter custom dimensions.
- Paint: press Ctrl+W (Resize), choose Pixels, keep “Maintain aspect ratio” ticked, and save as a new file.
On a Mac
Open the image in Preview, choose Tools → Adjust Size, make sure “Scale proportionally” is ticked, enter the width, and save. Use File → Export to save a copy in a different format or quality.
On iPhone and Android
Phones don’t have a simple resize option in their photo apps. Use the image resizer in Safari or Chrome, or on iPhone, build a short Shortcuts automation with the “Resize Image” action if you do it often.
How to avoid losing quality
- Keep proportions locked. Changing width and height independently stretches the picture.
- Shrink, don’t enlarge. Making an image smaller keeps it sharp. Making it bigger can’t create detail, so it turns soft.
- Resize from the original, not from a copy that’s already been shrunk and compressed several times.
- Choose the right format. JPG or WebP for photos, PNG for screenshots, logos and graphics with text.
- Need a different shape? Crop first with the image cropper, then resize.
Resizing to a file size (KB or MB)
File size depends on both dimensions and compression. To get under a limit like 100 KB, first reduce the width and height to what’s actually needed, then lower the JPG quality. The resizer does the quality step automatically when you enter a maximum size. For files that are already the right dimensions, the image compressor shrinks them without resizing.
Common sizes
| Use | Size in pixels |
|---|---|
| Instagram square post | 1080 × 1080 |
| Instagram portrait post | 1080 × 1350 |
| Link preview (Open Graph) | 1200 × 630 |
| YouTube thumbnail | 1280 × 720 |
| Blog content image | 1200–1600 wide |
| 2 × 2 inch photo at 300 DPI | 600 × 600 |
Platforms adjust their recommendations from time to time, so check the current guidance when it really matters.
Common questions
- What’s the difference between resizing and compressing? Resizing changes the number of pixels; compressing keeps the pixels but stores them more efficiently. Both make files smaller.
- What does DPI mean for resizing? DPI only matters for printing. On screens, only the pixel dimensions count. For print, multiply inches by 300 to get the pixels you need.