Online Tool Store
Image Resizer
Resize a JPG, PNG, or WebP image by an exact pixel width and height or by a percentage scale, with an aspect-ratio lock to avoid stretching. Runs entirely in your browser.
This works right here on your device — nothing gets sent out.
Sample image — choose your own file to replace it.
How it works
- Choose a JPG, PNG, or WebP image.
- Pick "By percentage" (with 25%, 50%, 75% and 150% shortcuts) to scale proportionally, or "By pixels" for an exact size or a common width like 1920 px.
- Choose the output format and, for JPG or WebP, the quality.
- Compare the original and resized dimensions side by side.
- Click Download resized image to save the result.
How resizing works
The image is drawn onto an off-screen canvas at the target width and height using
ctx.drawImage(),
which resamples every pixel to fit the new size, then the browser's own encoder
(canvas.toBlob())
saves it back out in the original format — the same resampling a photo editor does
when you set a custom width and height.
FAQ
Is my image uploaded anywhere?
No. The image is decoded and redrawn locally in your browser using the Canvas API — it never leaves your device.
What's the difference between resizing by percentage and by pixels?
By percentage scales the image relative to its current size — 50% halves both dimensions, 200% doubles them. By pixels lets you type an exact width and height instead, which is handy when a site or form asks for a specific size like 1200×630.
What does "Lock aspect ratio" do?
With it on, changing the width automatically recalculates the height (and vice versa) to keep the image's original proportions, so it doesn't come out stretched or squashed. Turn it off if you deliberately want a different aspect ratio.
Which formats are supported?
JPG, PNG, and WebP go in. By default the resized file keeps the same format, and you can switch the output to JPG, PNG, or WebP.
How do I make the file smaller as well as resizing it?
Lower the pixel size and, for JPG or WebP output, lower the Quality slider. PNG is lossless, so its quality slider is turned off and its size depends on the pixel dimensions. The Original and Resized panels show the file size so you can compare.
What happens to transparent areas if I save a PNG as a JPG?
JPG cannot store transparency, so transparent areas are filled with white before saving. If you need to keep transparency, use PNG or WebP output.
Is there a maximum size?
Each side can be up to 16,384 pixels. Browsers cannot reliably build larger images, so a bigger value shows a clear message instead of a failed download.
Can I make an image bigger, not just smaller?
Yes — percentages above 100% and pixel values larger than the original both work. Keep in mind that enlarging a photo doesn't add real detail, so very large increases can look soft or blocky.
How we compare
| Feature | Online Tool Store | ResizeImage.io | Img2Go | iLoveIMG |
|---|---|---|---|---|
| Image stays on your device | ✓ | Processed locally | Uploaded (encrypted) | Server-side processing |
| Resize by exact pixels or percentage | ✓ | Yes | Yes | Yes |
| Quick presets | 25/50/75/150% and common widths | Standard sizes and social presets | Device and social presets | 25%, 50%, 75% |
| Choose JPG, PNG or WebP output with a quality slider | ✓ | JPG, PNG, WebP, TIFF, GIF | 9 formats | Not listed |
| No sign-up, no daily file limit | ✓ | No sign-up | Free daily file limit | Login available |
ResizeImage.io, Img2Go and iLoveIMG also resize in batches, and ResizeImage.io adds physical units and a target file size, which this tool doesn't. Choose Image Resizer for a quick single-image resize by percentage or exact pixels, with your choice of format and quality, where the file never leaves your device.