PDF Medic OnlineResize image
Change a picture’s width and height in pixels, or by percent, without stretching it.
Files never leave your device
How to Resize image
- Press Choose pictures, or drop them on the box above. The size of the first picture is shown in pixels.
- Under How, pick By percent and type a number, or pick Exact size and type a width or a height.
- Leave Keep the shape (no stretching) ticked unless you really want the picture stretched.
- Press Resize, then Download (or Download all (ZIP) for several pictures).
By percent or exact size
By percent is the quick way: 50 (the starting value) halves the width and the height, 25 makes the picture a quarter as wide and tall, and 200 doubles it. Any number from 1 to 1000 works. Width and height change together, so the shape never changes.
Exact size is for when a form, a website or a printer asks for a number of pixels. With Keep the shape ticked, type only the width or only the height and the other follows. If you type both, the picture is made as large as possible while fitting inside both, so one side may come out smaller than you typed. Untick Keep the shape to get exactly the width and height you typed; the picture is then stretched or squeezed to match. A box you leave empty keeps the original value.
Getting an exact size like 600 × 600 without stretching
A picture can only reach a new width and height without stretching if both have the same shape. So when the shapes differ, crop first: open Crop image, pick the shape you need (1:1 for a square), keep the part you want, and download it. Then come back here, choose Exact size and type just the width. The height will follow and match.
This tool works in pixels only. If a form gives a size in centimetres, inches or DPI, use the pixel size the form states, if it gives one; the tool has no DPI setting.
Making a picture bigger
You can enlarge a picture, up to 1000% or to any pixel size, but enlarging cannot add detail that was never there: the result is bigger but softer. Browsers can only draw about 16 megapixels at once (for example about 4900 × 3260 pixels), so a larger result is kept within that limit, with its shape unchanged, and a note tells you.
What you get back
Fewer pixels usually means a smaller file, but resizing does not aim for a size in KB. If a form gives a KB limit, use Compress image with Fit a size instead; it reduces the pixels too when it has to.
When it is done, you see the new width and height (for one picture) and the total file size before and after, so you can check the result before you download it. Your original pictures are not changed.
- PNG pictures stay PNG, with their see-through areas. WebP stays WebP when your browser can save WebP; otherwise it becomes JPG.
- JPG, HEIC, GIF and other pictures are saved as JPG at high quality (92 out of 100). Any transparent areas turn white. An animated GIF keeps only its first frame.
- The new size is added to the file name, for example photo-600x450.jpg.
- The hidden details a phone stores in a photo, such as the date and the GPS location, are not copied into the resized file, and the photo is saved upright.
- iPhone HEIC photos open only in browsers that can read HEIC, such as Safari on iPhone, iPad and Mac.
Everything happens in your browser: your file is never uploaded to any server. You can check: once your file is open, turn on airplane mode — the tool still works.
Questions
How do I resize an image to 600 × 600 pixels?
If the picture is not square, crop it to 1:1 with Crop image first. Then choose Exact size here and type 600 as the width; the height becomes 600 too. Typing 600 in both boxes without cropping makes the longer side 600 and the other side shorter.
Can I resize many pictures at once?
Yes. Choose them together or use Add more. The same setting is used for each, and each keeps its own shape. Download all (ZIP) saves them together.
Will resizing make my photo blurry?
Making it smaller keeps it sharp at its new size. Making it bigger spreads the same detail over more pixels, so it looks softer, more so the more you enlarge it.
How do I resize an image in KB, not pixels?
Use Compress image and choose Fit a size. Type the limit in KB, and it finds the best quality that fits, making the picture smaller in pixels only if it has to.
Can I set the size in centimetres or DPI?
No. The tool uses pixels only. Use the pixel size your form or printer asks for.
Is my file uploaded?
No. Resize image runs in your browser on your own device. The file is never sent to our server or anyone else. Once your file is open you can even turn on airplane mode.
Is it free?
Yes. No sign-up, no limits on how many files, and no watermark is added to your file.
Does it work on a phone?
Yes, in any modern browser on iPhone, Android, Mac, Windows or Linux. Very large files work best on a computer, because a phone browser has less memory.