Are my files uploaded to a server?

No. This conversion runs inside your browser using your own device’s processing power, and the file is not uploaded. Once a tool has been used once (video, text recognition and background removal download their engine from this site the first time), it keeps working when your connection drops.

Is the transparency kept?

Yes. WebP supports an alpha channel, so transparent areas stay transparent — the main reason to choose it over JPG.

How much smaller will the file be?

It depends on the picture. Without a size limit the WebP is lossless, which usually stores the same pixels in fewer bytes than PNG; the result shows the new size next to the original, and if a file did not get smaller, keep the PNG. With a size limit, the colours are compressed with loss until the file fits.

Convert PNG to WebP

Runs on your device · Your file never leaves your device.

WebP keeps the transparency PNG is used for, and in its lossless mode stores exactly the same pixels in what is usually a smaller file, so it suits logos, icons and graphics on a web page.

Unlike converting a transparent PNG to JPG — which fills the transparent areas with white — WebP preserves the transparent background intact.

Batch convert a set of graphics at once, entirely on your device, with an optional size cap.

How to convert PNG to WebP

Add your PNG graphics, icons or screenshots.
Press Convert — the transparent background is preserved.
Download the smaller files, as a ZIP for a batch.

Supported formats and limits

Input: PNG images
Output: Lossless WebP with transparency intact (lossy only when a size limit needs it)
Saving: Usually smaller; each result shows its size next to the original
Transparency: Kept — the main reason to choose WebP over JPG
Where it runs: In your browser; nothing uploaded

Not for: Print or archival masters — keep the original PNG for those and use WebP on the web.

Lossless unless you set a size limit

WebP has two modes: lossless, which keeps every pixel as PNG does, and lossy, which approximates colours as JPG does. Without a size limit, this page uses the lossless mode: every pixel and every level of transparency is kept exactly, and the result card says “Lossless”. The quality slider is hidden then, because there is nothing to approximate.

The file is usually smaller than the PNG, but not always. The result shows the new size next to the original, so if a file did not get smaller, keep the PNG.

What changes when a size limit is on

With Force a maximum file size on, the lossless version is tried first and kept if it fits. If it does not, the picture is encoded lossily, starting at the slider’s quality and going down to 40, and only then is the pixel size reduced; /compress-image explains the steps. The transparency is still kept at full quality in the lossy mode; it is the colours that are approximated.

Lossy WebP always stores colour at half the resolution of brightness. On photographs this is hard to see; on a screenshot with small red or blue text, or a logo with thin coloured lines, edges can look soft or fringed. The quality score is measured on brightness only, so look at the after preview too before replacing the original.

Very long images

WebP cannot store a picture wider or taller than 16,383 pixels. Full-page screenshots of long websites are the PNGs that most often go beyond it; such a picture is scaled down to fit, and its result says so. If every pixel of a very long screenshot matters, keep it as PNG.

Frequently asked questions

Are my files uploaded to a server?: No. This conversion runs inside your browser using your own device’s processing power, and the file is not uploaded. Once a tool has been used once (video, text recognition and background removal download their engine from this site the first time), it keeps working when your connection drops.
Is the transparency kept?: Yes. WebP supports an alpha channel, so transparent areas stay transparent — the main reason to choose it over JPG.
How much smaller will the file be?: It depends on the picture. Without a size limit the WebP is lossless, which usually stores the same pixels in fewer bytes than PNG; the result shows the new size next to the original, and if a file did not get smaller, keep the PNG. With a size limit, the colours are compressed with loss until the file fits.