Filewhisk

Convert PNG images to WebP

This free online PNG to WebP converter compresses the same image significantly smaller while keeping transparency intact, which is why most sites serve images in WebP today. Drop in a PNG and get back a WebP — one at a time or a whole batch, downloaded as a ZIP. Nothing is uploaded; the conversion happens entirely on your device.

No upload No file size limit No sign-up Free

Drop PNG images here

or click to choose — .png, any number of files

Why PNG files end up bigger than they need to be

PNG compresses losslessly, which is exactly why it can end up large: it has to store enough information to reproduce every pixel exactly, with no shortcuts. That is the right trade for some things - a screenshot with sharp text, a logo with flat colour fields - and an expensive one for others, especially images with a lot of fine detail or gradients sitting behind a transparent area. WebP was designed specifically to close that gap without asking you to give up the transparency PNG is often chosen for in the first place.

What actually changes in the conversion

PNGWebP (this tool's output)
TransparencyYesYes — kept
Typical sizeBaseline25–35% smaller, often more
CompressionAlways losslessLossy here, at high quality
Browser supportUniversalUniversal in current browsers

Transparency survives the trip unchanged - a transparent PNG produces a transparent WebP, not one with a background colour filled in. The only real change is compression: this tool uses WebP's lossy mode at a high quality level, which produces meaningfully smaller files than a true lossless WebP would, at a quality cost that is not visible in normal viewing.

If you need output that is provably pixel-identical to the source - not just visually indistinguishable - keep the file as PNG. Lossy WebP at high quality is the better choice for the overwhelming majority of real use, but it is still a compression trade, not a guarantee of zero change.

When this trade is worth making

WebP earns its keep specifically inside browser contexts: a website's images, a web app's assets, anything where the file will be fetched and displayed by a browser that already supports it. Smaller files there mean faster loads without any visible quality cost. Outside a browser - printer software, older desktop editors, some phone gallery apps, upload forms locked to a specific format list - WebP support is still inconsistent, so PNG remains the safer choice for anything leaving the web.

A whole folder at once

Drop in as many PNG files as you have and each converts independently, with a single ZIP download once they are all done. There is no file count limit, since nothing is uploaded to a server that would need to handle the load.

Nothing is uploaded

Both the decoding and the encoding happen entirely inside your browser using canvas. The images never leave your device.

Frequently asked questions

How much smaller will the file actually be?

It depends heavily on the image, but WebP typically produces files 25-35% smaller than PNG at visually comparable quality, and often much more for photographic content with a transparent background. A PNG with large flat areas of a single colour compresses well already, so the gap there is usually narrower than for a busy or photo-like image.

Will my transparency survive the conversion?

Yes. WebP supports an alpha channel the same way PNG does, and it is kept through the conversion - a transparent PNG produces a transparent WebP, not one with a solid background filled in.

Is the quality setting here lossless or lossy?

Lossy, at a high quality level by default. WebP does have a genuine lossless mode, but it typically produces larger files than lossy WebP at a quality setting high enough that the difference is not visible - for most uses, high-quality lossy WebP is the better trade. If you specifically need pixel-perfect output with no compression artifacts at all, keep the file as PNG instead.

Why would I convert to WebP instead of just keeping the PNG?

Smaller files mean faster page loads if the image is going on a website, less storage if you are keeping a large batch, and quicker uploads anywhere file size matters. The trade-off is compatibility outside browsers - see the next question - so it makes most sense for images that are staying inside a browser context: a website, a web app, an email that will be viewed in a browser-based client.

Does every browser support WebP?

Every current major browser displays WebP without issue. The gap is outside browsers - some older desktop software, printer upload portals and phone apps still do not recognise it, which is the reverse situation of this converter (see the WebP to PNG tool if you need to go the other direction for exactly that reason).

Are my images uploaded to convert them?

No. Decoding the PNG and encoding the WebP both happen entirely inside your browser. Nothing is sent to a server, and there is no file size limit beyond what your device can hold in memory.

Compress Image to Target Size Hit an exact KB target for uploads and forms. Resize Image Exact pixels or a percentage, with aspect ratio locked. Convert Image Format PNG, JPG, WebP and AVIF, in both directions. Rotate Image Quarter turns, free angles and mirror flips. Crop Image Drag the frame, or type exact pixel values. Circle Crop Image Round avatars with a real transparent background.