WebP to PDF Converter

1Drop your WebP files inIt never leaves your machine.

2Set the pageEverything updates as you change it.

3Build and downloadAssembled here and saved from your own browser.

A format the page can already read

WebP decodes natively in the browser, so nothing extra has to load. Transparency survives, and opaque images are re-encoded to keep the document small.

How to use this tool

Drop your WebP files onto the box at the top, or click it to browse. Each becomes a page, in the order the thumbnails show, and you can drag a thumbnail onto another to move it.

Set the paper and margin, then check the preview. The dashed line shows the margin, and each thumbnail carries the effective print resolution of that image at the size you have chosen.

If your WebP files have transparency, the background setting decides whether it survives or gets filled in.

The real reason to convert WebP

WebP is a good format. It compresses better than JPEG at the same visual quality, it does transparency like PNG, and it does animation like GIF. On paper there is no reason to convert it to anything.

The problem is not the format, it is everything that has to open it. Browsers handle WebP universally now, but browsers were never the difficulty. The difficulty is the print shop whose workflow was set up years ago, the document management system your client uses, the desktop software someone has not updated since two operating systems ago, the email client that shows a broken icon.

So converting WebP is usually not about quality or size at all. It is about handing someone a file they can definitely open. PDF is close to universal in a way no image format is, which is why it keeps being the answer when a file has to cross an organisational boundary.

Worth knowing: you will not gain anything in size. A PDF built from WebP images is normally larger than the WebP files were, because WebP compresses better than what goes inside a PDF. You are trading a little size for the certainty that it opens.

Lossy and lossless are both called WebP

WebP is really two formats wearing one name. Lossy WebP is the JPEG competitor, built for photographs. Lossless WebP is the PNG competitor, built for flat colour and sharp edges, and it can carry transparency.

That matters for what happens on the way into the PDF. An image with an alpha channel is embedded as PNG, which is lossless, so nothing is thrown away. Everything else is re-encoded as JPEG at the quality you set.

Re-encoding a lossy WebP as a JPEG means two different compression schemes have now been applied to the same picture, and each one throws away slightly different things. On a photograph at reasonable quality this is invisible. On something already squeezed hard to save bandwidth, the second pass can make the artefacts from the first pass more obvious. If the source was already small for its dimensions, push the quality up.

A worked check you can repeat

Take a 3000 by 2000 pixel image onto A4 portrait with a 10 mm margin, set to Whole image.

A4 is 595.28 by 841.89 points. The margin is 10 times 72 divided by 25.4, which is 28.35 points a side, leaving 538.59 by 785.20. The image aspect ratio is 1.5 against a box of 0.686, so width limits it and the scale is 538.59 divided by 3000, or 0.17953.

The picture lands 538.59 wide by 359.06 tall, filling the width and centred vertically with 213.07 points above and below. Effective resolution is 3000 pixels across 7.48 inches, about 401 dpi, well past the print threshold.

Every figure above was checked against an independent implementation before publishing, along with the page presets against their real dimensions, orientation switching, the fill and stretch modes and margins larger than the paper.

Mistakes that catch people out

Expecting the PDF to be smaller. It usually will not be. WebP is more efficient than what a PDF can hold internally, so you are converting for compatibility, not size.

Converting an already heavily compressed WebP at low quality. Two rounds of lossy compression compound. If the file was tiny for its dimensions, raise the quality to compensate.

Assuming transparency comes through by default. It comes through if you ask for it. Pick a solid background for anything going to print, since transparent areas take the colour of whatever is behind them.

Forcing one orientation across a mixed set. Leave orientation on match each image and portrait and landscape files both come out correctly.

Turning quality up to fix a soft image. Quality controls compression damage, not pixel count. If the badge says 73 dpi, use a smaller page or a bigger original.

Common questions

Is my WebP uploaded anywhere?

No. The images are read by your browser, the PDF is assembled here on the page, and the download comes from your own machine. Nothing crosses the network, so there is nothing on a server to store or delete.

Why convert WebP to PDF at all?

Because WebP is still not universally supported. Plenty of older software, print shops, document management systems and email clients will not open a WebP, and every one of them will open a PDF. Converting is often about making a file someone else can actually receive.

Does WebP keep transparency?

Yes, WebP supports an alpha channel like PNG does. Pick the transparent background to keep it, or any colour to fill it in. Choose a solid colour for anything going to print.

Will the image get worse?

A lossy WebP re-encoded as JPEG loses a little, because it is being compressed twice by two different methods. A lossless WebP with transparency is kept as PNG and loses nothing. Turn the quality up if the source was already heavily compressed.

Why do my WebP files not open on my computer?

Support arrived at different times in different places. Modern browsers all handle it, but desktop software, older operating systems and many corporate systems lag well behind. That gap is the reason this tool exists.

Can I mix WebP with other formats?

Yes. Drop in JPG, PNG, GIF and BMP alongside them and they all become pages in the same document, in whatever order you arrange the thumbnails.

Related PDF tools and reference

Reference: ISO 216, the standard that defines the A series paper sizes used here.