Resize an image

Set exact pixel dimensions or aim for a target file size in KB. Everything runs in your browser.

Resize a JPG, PNG or WEBP to exact pixel dimensions, or hit a target file size in KB directly — the tool encodes and re-measures until it actually lands there.

Processed in your browser

Drop your image here

or choose an image from your device

Choose an image

Accepts JPG, PNG or WEBP · No fixed size limit — we adapt to what your device can handle. Very large files may take longer or show a warning.

About Resize Image

Two different resize modes

Dimension mode scales the image to the width and height you type, with the aspect ratio linked by default so nothing stretches. Target-size mode takes a KB figure instead and searches for the quality setting that produces a file under that limit — encoding, measuring the real byte count, and adjusting, rather than estimating.

Why resizing matters more than compressing for most oversized images

File size scales roughly with the square of pixel dimensions. Halving both width and height typically removes about 75% of the pixels — and the bytes — with zero visible loss on a page that never displayed the extra pixels anyway. That's usually a bigger win than any quality slider.

Settings and output

Pixel dimensions vs target size

Use pixel dimensions when you know the exact width or height a layout needs. Use target size when a form or platform imposes a KB cap and you don't want to guess at quality values manually.

Aspect ratio lock

On by default so typing a width automatically computes the matching height. Turn it off only when you deliberately need a non-proportional size, and expect visible stretching.

When to use it

Scaling a large camera photo down to the size it will actually be displayed at on a website.
Hitting a strict KB limit for an upload form without trial-and-error quality guessing.
Preparing a batch of images to a consistent pixel width before publishing.

Limitations to know

Upscaling a small image adds no real detail — it interpolates existing pixels into a bigger, softer file.
Target-size mode can't beat physics: an impossible target for the current dimensions needs a smaller width first.
Unlinking the aspect ratio and entering mismatched numbers will visibly distort the image.

Common problems and fixes

It can't reach my target KB.

The pixel dimensions are too large for that byte budget at any reasonable quality. Reduce the width first, then try the target size again, rather than letting quality drop into the twenties.

My resized image looks stretched.

The aspect ratio lock was off and the width/height you entered don't match the original ratio. Re-enable the lock and enter only one dimension.

The image looks softer after making it bigger.

Upscaling can't add detail that wasn't captured originally — it's interpolating existing pixels. Start from the highest-resolution original available instead.

How to use it

1Drop your image. Its current pixel dimensions appear in the metadata row.
2Resize by pixels — type a width or height and the other side follows the aspect ratio — or switch to target size and enter the KB limit you need to hit.
3In target-KB mode the tool encodes, measures, adjusts quality and repeats until the output actually fits under your limit.
4Press Resize, verify the output dimensions in the result panel, and download.

Frequently asked questions

What width should I use for a website?

1600px on the long edge for a full-width hero, 1200px for body images, around 800px for cards and thumbnails. Serving pixels wider than the display area is the most common cause of slow pages.

Can I make a small image bigger?

You can enter larger numbers, but nothing is gained — upscaling interpolates existing pixels and produces a bigger, softer file. Start from the highest-resolution original you have.

How does the target file size mode work?

It runs a binary search on encoder quality: encode, measure the real byte count, adjust, repeat. That's why it lands under your limit instead of estimating.

It can't reach my target KB. What now?

The dimensions are too large for that limit. Reduce the width first — halving it removes roughly three quarters of the pixels — then try the target again rather than pushing quality into the twenties.

Is the aspect ratio always locked?

The linked ratio is on by default so images don't stretch. Unlink it if you deliberately need a non-proportional size, and expect distortion.

Related guides

Not sure which settings this image needs? Run it through the image optimization tool to get an optimization score and automatic format, quality and size choices.