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 tool runs entirely in your browser. Your files are never uploaded to a server.
Sample image — choose your own file to replace it.
How it works
- Choose a JPG, PNG, or WebP image.
- Pick "By percentage" to scale proportionally, or "By pixels" for an exact size.
- 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. The resized file keeps the same format as the one you uploaded.
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 | Photoshop | Online resizer sites |
|---|---|---|---|
| No file upload — runs in your browser | ✓ | ✓ | ✗ |
| Free, no install or sign-up | ✓ | Paid subscription | ✓ |
| Resize by percentage or exact pixels | ✓ | ✓ | Often pixels only |
Photoshop is a full editor with far more control, but it's a paid install for a task that's usually this simple. Most online resizer sites upload your file to a server first. Image Resizer gets you an exact or proportional resize in one step, with the image never leaving your device.