Image resize & compress

Resize and compress images right in your browser.

Select an image or drag & drop here

You have a 4,000-pixel photo straight from a phone camera, and the form you are filling in wants something under 1 MB. Or a blog theme asks for a 1200x630 cover image and yours is the wrong shape. This tool changes an image's pixel size and re-encodes it at a quality level you choose, then hands the smaller file straight back to you.

How it works

Width, height and the ratio lock

Enter the pixel size you want in Width and Height. With Keep ratio ticked, typing one value fills in the other automatically so the picture is not stretched — this is what you want almost every time. Untick it only when a target size demands an exact shape and you accept the distortion. Leaving a field empty means that dimension is derived from the other one.

Enlarging is possible but rarely useful: scaling a 500px image up to 2000px does not create detail that was never captured, it just makes existing pixels bigger and softer. Resizing down is where the real savings are.

Picking an output format

Format	Best for	Transparency
JPEG	Photographs, widest compatibility	No
WebP	Photos and graphics on the web, smallest files	Yes
PNG	Logos, screenshots, flat colour, sharp edges	Yes

WebP typically produces a file 25–35% smaller than a JPEG of similar visual quality, and every current browser reads it. Choose PNG when hard edges and text must stay crisp, or when you need a transparent background — note that converting a transparent PNG to JPEG fills the empty area with solid colour.

The quality slider

Quality controls how aggressively JPEG and WebP throw away detail. Around 80% is the usual sweet spot: files shrink dramatically while differences stay hard to see at normal viewing size. Below roughly 60% you start to notice blocky patches in skies and smooth gradients. PNG is lossless, so the slider has no effect on it.

One thing to know: re-encoding a JPEG that was already compressed adds a second round of loss. If you have the original file, resize from that rather than from a copy that has been through several tools.

Where the work happens

The image is decoded and redrawn on an HTML canvas inside your own browser, then exported. Nothing is uploaded to a server, so private photos, ID scans and internal screenshots stay on your machine — and the tool keeps working with the network disconnected.

Terms explained

Pixel dimensions: The width and height of an image measured in pixels, such as 1920x1080. This is the image's actual size, separate from how large it appears on screen.
Keep ratio: A lock that preserves the original width-to-height proportion, so changing one dimension adjusts the other and the picture is not squashed.
Quality: A 0–100 setting for JPEG and WebP that trades visual detail for a smaller file. It has no effect on PNG output.
Lossy compression: Compression that permanently discards image data to save space. JPEG and WebP are lossy; PNG is lossless.
WebP: A modern image format supported by all current browsers that usually produces noticeably smaller files than JPEG at the same visible quality.

Frequently asked questions

Is my image uploaded anywhere?

No. The file is read, resized and re-encoded entirely inside your browser using the canvas API. It is never sent to a server, which is why the tool still works offline once the page has loaded.

Why is my resized file still large?

Two things usually explain it: the pixel dimensions are still bigger than you need, or the quality slider is set very high. Try halving the width and setting quality near 80%, and switch the format to WebP if you have not already.

Which format should I use for a website?

WebP for photographs and most images, since it gives the smallest file at a given quality and is universally supported now. Use PNG only for logos, diagrams and screenshots where sharp edges or transparency matter.

Does resizing reduce image quality?

Making an image smaller generally looks fine — you are discarding pixels you no longer need. Enlarging does reduce apparent quality, because the tool can only interpolate between existing pixels and cannot recover detail the camera never recorded.

Can I resize several images at once?

This tool handles one image per pass. For a batch, repeat the steps with the same width and quality settings, or use a desktop utility or command-line tool built for bulk conversion.