Resize Image by Percentage

Scale an image up or down by a percentage, no math required.

How to resize by percentage

Drop your image in and drag the slider — 100% keeps the original size, below 100% shrinks it, above 100% enlarges it. The new pixel dimensions update live as you drag, and the download is ready immediately.

For example, halving a photo to 50% is a quick way to cut file size roughly to a quarter without needing to calculate exact target pixel dimensions yourself.

Why percentage scaling is often simpler

Scaling by percentage means you never need to know or calculate the original image's exact pixel dimensions — 50% always gives you a version at exactly half the width and height, no matter what size you started with, which is the simplest way to shrink several differently sized photos down by the same proportion in one pass.

This makes percentage scaling especially useful for quickly lightening a batch of camera photos before emailing them, or halving a screenshot's size before pasting it into a document, without needing a calculator or looking up the source resolution first. If you do need an exact final size instead, the Resize by Pixels tool gives you direct control over the output width and height.

A quick way to lighten several photos

Because the percentage applies proportionally regardless of the original size, this is a fast way to shrink a handful of differently sized photos down by the same relative amount — useful before attaching several images to an email, or pasting a batch of screenshots into a document without them taking up excessive space.

The resize itself runs through the Canvas API directly in your browser, so each adjustment previews instantly with no upload wait, whether you're scaling one photo or working through several in a row.

Rules of thumb for common percentages

75% is a gentle trim that barely affects visual quality while shaving off a meaningful chunk of file size. 50% is the most common everyday choice, halving both dimensions and typically cutting file size to roughly a quarter of the original. Below 25%, most photos start losing enough detail that they're only really suitable as small thumbnails.

Frequently asked questions