Image Resizer

About the Image Resizer

Resize images by pixels (px) or percentage — exact width and height, aspect lock, instant preview. Free and private; nothing leaves your browser.

The image is resized locally with the Canvas API and never uploaded.

How to use the Image Resizer

Step 1Add an image. Its current dimensions appear in the size stat.
Step 2Type a width or height — the other updates automatically while “lock aspect ratio” is on.
Step 3Pick a percentage preset or an exact size, choose the output format, then resize and download.

When people reach for this tool

Hit an exact pixel width your layout expects

Templates, ad slots and CMS fields often reject anything but the exact dimensions. Resize to the number instead of guessing and re-exporting.

Produce one image at several sizes at once

Keep the aspect ratio locked and work through a standard ladder such as 320, 640, 1280 and 1920 pixels wide for a responsive gallery.

Bring an oversized file under a platform limit

When a form refuses an image for being too large, resizing to the documented maximum is often all that is required.

Practical tips

Lock the aspect ratio unless you have a deliberate reason to distort the picture — stretching usually looks like a mistake rather than a choice.
Resizing down cannot add detail. Going from 4000px to 600px looks fine; the reverse produces a soft, blocky image.

What you get

Exact pixel sizes or percentage presets (25/50/75/100%)
Locked aspect ratio by default
Live preview of the resized result
Output as JPG, PNG or WebP
100% local processing

Image Resizer — FAQ

What does “lock aspect ratio” do?

When enabled, changing the width automatically updates the height (and vice versa) so the image is never stretched or squashed.

Can I distort an image on purpose?

Yes — uncheck “lock aspect ratio” and enter a width and height independently.

Does resizing reduce quality?

Shrinking an image discards pixels and is barely noticeable. Enlarging it has no extra detail to work with, so the result looks softer than the original.

Why lock the aspect ratio?

Width and height are linked so the picture keeps its proportions. Turn the lock off only when you need an exact non-standard crop, for example a banner of a fixed size.