Does WebP keep transparency?

Yes. WebP supports an alpha channel, so transparent PNG areas stay transparent. This is the main reason to pick WebP over JPG when the image is not a plain rectangle photograph.

Is WebP supported everywhere?

In current browsers, yes. Older software outside the browser — some desktop viewers, older office suites and a few social platforms — may still refuse it, so keep a PNG or JPG copy for anything you send to other people.

Should I use quality 100?

Rarely. At 100 the encoder keeps almost everything and the file can end up larger than the PNG. Values between 75 and 90 usually look identical at normal viewing size while cutting the size substantially.

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PNG to WebP

Convert PNG images to WebP without losing transparency. Everything runs in your browser, so nothing is uploaded and nothing is stored.

Drop a PNG file here

It stays on your device — the conversion runs in this page, with no upload.

Choose a file

WebP was designed to replace both PNG and JPEG on the web: it keeps the alpha channel that PNG needs while compressing photographic content closer to how JPEG does. For a transparent image it is usually the smaller file with no visible difference, which is why it is worth converting assets that ship to browsers. The conversion runs on your machine and the original never leaves it.

How it is calculated

canvas.toBlob(callback, "image/webp", quality)

The browser re-encodes the decoded pixels as WebP. Because WebP keeps alpha, transparent areas pass through untouched and there is no background colour to choose.

Source: MDN HTMLCanvasElement.toBlob() — quality is a number between 0 and 1 for lossy formats

Questions people ask

Does WebP keep transparency?: Yes. WebP supports an alpha channel, so transparent PNG areas stay transparent. This is the main reason to pick WebP over JPG when the image is not a plain rectangle photograph.
Is WebP supported everywhere?: In current browsers, yes. Older software outside the browser — some desktop viewers, older office suites and a few social platforms — may still refuse it, so keep a PNG or JPG copy for anything you send to other people.
Should I use quality 100?: Rarely. At 100 the encoder keeps almost everything and the file can end up larger than the PNG. Values between 75 and 90 usually look identical at normal viewing size while cutting the size substantially.

Found a problem, or want more?

A number that disagrees with its source is a defect, not a rounding preference.

What did you enter, what did the tool show, and what did you expect instead? If you have a source that disagrees with ours, a link to it is the most useful thing you can send.

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