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Image Resizer

Resizing changes an image's pixel dimensions — useful when a photo is far larger than the space it will be shown in. Enter a width, a height or a percentage and the aspect ratio is kept for you. Resizing down also makes the file dramatically smaller, which is usually the real goal.

Runs entirely in your browser — your images are never uploaded.

How to

How to use the Image Resizer

  1. 1

    Add your images

    Drop in one or many. Each image's current dimensions are shown.

  2. 2

    Set the new size

    Type a width or height and the other follows automatically, or switch to percentage to scale everything proportionally.

  3. 3

    Choose the output format

    Keep the original format or convert while resizing — often worth doing, since WebP is smaller.

  4. 4

    Download

    Save individually or as a ZIP.

Examples

Image Resizer examples

Phone photo for a website

Input
4032 × 3024 photo, width set to 1600
Output
1600 × 1200, roughly 85% smaller

A 4000-pixel-wide photo is far larger than any web layout needs. Resizing to 1600 saves most of the file size with no visible loss on screen.

Scaling by percentage

Input
Mixed batch at 50%
Output
Each image halved in both dimensions

Percentage mode suits batches of different sizes, where one fixed width would distort the relationship between them.

Enlarging a small image

Input
300 × 200 upscaled to 1200 × 800
Output
Blurry, four times the pixels

Enlarging cannot invent detail that was never captured. The tool warns before upscaling, since the result is almost always worse.

Why use it

What the Image Resizer gives you

Aspect ratio kept by default

Change one dimension and the other follows, so images are never stretched unless you deliberately unlock the ratio.

High-quality downscaling

Resampling uses the browser's high-quality mode, which is noticeably cleaner than the default on large reductions.

Warns before upscaling

Enlarging past the original resolution only adds blur and bytes. You are told before it happens.

Presets for common targets

Sizes for social posts, web headers and thumbnails, so you do not have to remember them.

Runs locally

Resizing happens in your browser, so nothing is uploaded.

Good to know

Image Resizer limitations

  • Enlarging cannot add detail that was not in the original. Any upscale will look softer.
  • Resizing a lossy image re-encodes it, so a little quality is lost each time.
  • Animated images are flattened to their first frame.
  • Images are limited to 25 MB each.

Summary

Image Resizer in short

  • Resizing changes pixel dimensions; downscaling also shrinks the file substantially.
  • Keep the aspect ratio locked unless you specifically want a distorted image.
  • Most web layouts need no more than about 1600 pixels wide.
  • Enlarging cannot recover detail and always looks softer.

FAQ

Image Resizer questions

What size should my images be for a website?

Around 1600 pixels wide covers full-width images on most layouts, including high-density screens. Content images usually need 800–1200, and thumbnails 300–400. Anything larger is bytes the visitor downloads and never sees.

What is the aspect ratio and why lock it?

It is the relationship between width and height. Locking it means changing one dimension adjusts the other automatically, so the image keeps its proportions. Unlocking lets you set both independently, which stretches the picture.

Can I make a small image bigger without losing quality?

No. The detail simply is not there to recover — enlarging spreads existing pixels over a larger area and interpolates between them, which always looks softer. AI upscalers guess at detail, which is a different thing from recovering it.

Should I resize or compress?

Resize first, then compress. Reducing dimensions removes pixels entirely and usually saves far more than compression alone, and compressing afterwards has less work to do.

Does resizing lose quality?

Downscaling discards pixels but generally looks clean, often sharper than the original at the smaller size. The re-encode that follows costs a little quality if the output is lossy.

How do I resize images of different sizes together?

Use percentage mode, which scales each image relative to itself. A fixed width would force very different images to the same dimension regardless of their shape.

What is the difference between resizing and cropping?

Resizing scales the whole image to new dimensions and keeps everything in frame. Cropping cuts parts away to change the framing or the aspect ratio. Use the Image Cropper when you need a specific shape.

What about DPI or PPI?

DPI only matters for printing. On screen, only the pixel dimensions count — a 1600-pixel-wide image is identical at 72 or 300 DPI. Set the physical size in your print software instead.

Do my images leave my computer when resizing?

No. The image is decoded and redrawn at the new size by your own browser. Nothing is uploaded, which matters for screenshots of internal dashboards or anything under an NDA.

Discover

Related image tools

Image CompressorCompress JPG, PNG and WebP images in your browser. Set a quality level or a target size and see exactly how much you saved.Image CropperCrop images to any aspect ratio with a drag handle and live preview. Presets for square, 16:9 and social sizes. Runs in your browser.Image ConverterConvert images between JPG, PNG, WebP and AVIF in your browser. Batch convert, control quality, and download as a ZIP.WebP ConverterConvert JPG and PNG images to WebP, or WebP back to JPG and PNG. Batch convert with quality control, all in your browser.