Why should I use WebP instead of JPEG or PNG?

WebP generally produces smaller files at the same visual quality, supports transparency like PNG, and is supported by every current major browser. For web performance it is usually the best default.

Does converting to WebP lose quality?

WebP supports both lossy and lossless modes. The tool shows you the measured before/after sizes and, where a conversion is lossy, says so explicitly before you run it.

Do my images get uploaded during conversion?

No. Your browser encodes WebP natively, so the conversion happens on your device. There is no server involved in processing at any point.

Which browsers can create WebP files?

Chrome, Edge, Firefox and Safari 16+ can encode WebP. The tool checks your browser first and tells you plainly if encoding is not available in yours.

Compress and convert WebP images — locally

WebP usually delivers the smallest images at good visual quality. Optimize existing WebP files or convert your JPG and PNG images to WebP — all inside your browser, with no upload step.

Open the WebP compressor tool Runs entirely in your browser — files never leave your device.

What this tool does

Converting JPEG photos or PNG graphics to WebP typically cuts file size meaningfully at comparable quality, because WebP uses a more modern compression method. This tool performs the conversion with the encoder built into your browser, so there is nothing to install and nowhere for your images to go.

You can also re-encode existing WebP files at a different quality, or resize them. If your browser cannot encode WebP (some older Safari versions lack the encoder), the tool detects that and tells you honestly instead of producing a fake result.

How to convert images to WebP without uploading

Add your images. JPG, PNG or existing WebP files — drop them into the home-page tool.
Choose WebP output. Select the WebP target and a quality preset that suits your use case.
Save the results. Converted files download straight from your browser, sizes compared honestly.

Supported operations

This list is generated from CompressKit's capability registry — only implemented and tested operations appear here.

Reduce file size

Re-encode the WebP at a different quality level.
Convert format

Convert from JPG or PNG to WebP (or from WebP back to PNG/JPEG when a compatibility target is needed).
Resize

Scale dimensions down — WebP at reduced resolution is the standard recipe for lightweight web images.

Frequently asked questions

Why should I use WebP instead of JPEG or PNG?: WebP generally produces smaller files at the same visual quality, supports transparency like PNG, and is supported by every current major browser. For web performance it is usually the best default.
Does converting to WebP lose quality?: WebP supports both lossy and lossless modes. The tool shows you the measured before/after sizes and, where a conversion is lossy, says so explicitly before you run it.
Do my images get uploaded during conversion?: No. Your browser encodes WebP natively, so the conversion happens on your device. There is no server involved in processing at any point.
Which browsers can create WebP files?: Chrome, Edge, Firefox and Safari 16+ can encode WebP. The tool checks your browser first and tells you plainly if encoding is not available in yours.

Ready to try it?

The WebP compressor tool runs on this site with no upload step — your file is processed by your own browser and saved back to your device.

Open the WebP compressor tool