What this image resizer does
The resizer changes the pixel dimensions of your pictures. Type an exact width or height, or switch to percentage mode to shrink or enlarge everything by the same factor. With the aspect ratio lock on, changing one dimension fills in the other automatically so nothing looks stretched. Add several images and the same rule is applied to each one, using each picture's own proportions. Results appear instantly with their new size in pixels and in kilobytes, and you can save them individually or as one ZIP.
When to use it
- Meeting a stated size for a profile photo, banner, marketplace listing or application form.
- Making a 12-megapixel phone photo suitable for a blog column or newsletter.
- Creating thumbnails and gallery previews in bulk.
- Reducing a screenshot so it fits in a document or chat message.
Tips for sharp results
Making an image smaller almost always looks good, because the browser averages many source pixels into each new one. The tool shrinks large pictures in several gentle steps instead of one jump, which keeps edges clean. Making an image larger is different: no software can invent detail that was never captured, so enlargements above roughly 150 percent look soft. If you must enlarge, do it once and avoid sharpening afterwards.
Decide the target size from where the image will be shown. For a full-width web hero, 1920 pixels is generous. For a content column, 800 to 1200 is plenty. For high-density screens you may want twice the displayed width. Keep the lock on unless you intentionally want to distort the picture or fit a fixed frame, and consider the crop tool when the frame has a different shape from your photo.
Format matters too. Choose JPEG or WebP for photographs and keep PNG for graphics with transparency or text. If you leave the output on "Same as original", a JPEG stays a JPEG and a PNG stays a PNG.
Worked example: a 4000 × 3000 photo for a blog column
Say photo.jpg is 4000 × 3000 pixels and your blog column is 1200 pixels wide. Type 1200 in the width box with Keep aspect ratio ticked and the height fills in as 900, because 3000 × 1200 ÷ 4000 = 900. The tool first halves the picture to 2000 × 1500, then draws the final 1200 × 900, and names the file photo-1200x900.jpg. If you type a height of 1080 instead, the width becomes 1440. In percentage mode, 25 percent turns the same photo into 1000 × 750. At 1200 × 900 the picture has 1,080,000 pixels instead of 12,000,000, which is why resizing is often the biggest single saving before you compress.
Privacy: nothing leaves your browser
All resizing happens locally on your device using the canvas API. Your images are never sent to a server, so confidential documents, ID photos and client work stay private. The page also works offline once it has loaded. The output files are freshly drawn, so embedded metadata such as location tags is not carried over.
Frequently asked questions
How do I resize an image without losing the aspect ratio?
Leave "Keep aspect ratio" ticked. Enter either the width or the height and the other value is calculated from the original proportions.
Can I resize many images at once?
Yes. Add as many images as you like, set the size once, and every image is processed. When there are two or more results, a button appears to download them all as a ZIP.
What is the difference between pixels and percentage mode?
Pixel mode gives every image the same target width or height. Percentage mode keeps each image relative to its own size, so a 4000 px photo and a 1000 px photo at 50% become 2000 px and 500 px.
Will resizing change the file format?
Only if you choose a different format. With "Same as original", JPEG, PNG and WebP files keep their type; other formats such as GIF or BMP are saved as PNG.
Is there a maximum output size?
Browsers limit canvas dimensions, so the tool allows up to 16,384 pixels per side and 80 megapixels in total. Larger requests show an error on that image instead of freezing your tab.