How to convert WebP to JPG in your browser

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You saved a picture from a website, or someone sent you one, and it is a .webp file that your editor, form or email program will not accept. This is a step-by-step guide to getting a JPG from it, with the three things worth checking on the way: transparency, size and quality.

Step 1: check that you need a JPG

A WebP is not a broken file. MDN describes WebP as having broad support in the latest versions of major browsers, but not deep historical support, which is why older software and upload forms can refuse it. A JPG is the format nearly everything accepts, so converting is a reasonable fix when a destination names JPG only.

If the destination also accepts PNG and your image has a transparent background, skip to the WebP to PNG guide instead. That route keeps the see-through areas.

Step 2: open the tool and add the file

Go to WebP to JPG and choose the file, or drag it onto the page. The tool handles one image at a time, up to 50 MB and 40 megapixels. The conversion runs in your browser, and the file contents are not uploaded to ConvertMango's conversion service.

If the picture is animated, expect only a still result. The tools are built for single images, so do not rely on them to keep movement.

Step 3: look at the background first

This is the step people skip. MDN states plainly that JPEG does not support an alpha channel, while WebP supports transparency. When a WebP with a clear background goes to JPG, those areas must become a colour, and our tool fills them white.

Think through what that does:

• A cut-out product shot gets a white background, which is usually what a shop upload wants.
• A white or very pale logo on transparent turns white on white and disappears.
• A soft shadow fades to white, which looks right on a white page and boxy on a coloured one.

If you need a different colour, place the image on that colour in an editor before converting. If you need transparency, JPG is the wrong destination.

Step 4: convert and download

Start the conversion and save the result. The tool asks the browser for JPEG quality 0.92 and offers no slider. MDN's documentation for the canvas export method describes that quality value as a number from 0 to 1 that applies to lossy formats, and says that if it is omitted or out of range the browser uses its own default. Different browsers use different encoders, so the same file can come out a slightly different size in different places.

Step 5: compare the result with the original

Open both files and zoom in on edges, text and smooth gradients. Then check the sizes. Do not be surprised if the JPG is larger. Google's FAQ says WebP typically achieves an average of 30% more compression than JPEG, and MDN reports lossy WebP files as 25 to 35% smaller on average at visually similar quality. Those are published averages from their own testing, not a promise for your picture, but they explain the direction: the same picture in a less efficient format tends to weigh more.

What I measured

To see the effect on one case, I generated a 1600 x 1063 pixel photo-like image (a CC0 licensed photograph, resized by script), saved it as lossy WebP at Pillow quality 92, then decoded that file and saved it again as PNG and as JPG at quality 92. This is an illustration with Pillow 11.3.0 and libwebp 1.5.0, not a benchmark, and browser encoders will differ.

So the JPG was bigger than the WebP here, but far smaller than a PNG would have been. If a photograph is going into a form that rejects WebP, JPG is the sensible landing spot; PNG would be a very heavy choice.

Step 6: keep both files

Keep the WebP. The JPG is a copy for a particular purpose, and because it was made from a lossy source, converting back to WebP later will not restore anything. Name them so you can tell them apart, and edit from the best version you have, exporting a fresh JPG each time instead of re-saving an old one.

When not to convert

• The destination already accepts WebP. Converting costs quality for no gain.
• The image has transparency you need. Use WebP to PNG.
• It is a screenshot, logo or line drawing. MDN advises lossless encoding for diagrams, logos and line art, because lossy compression gives unsatisfactory results on sharp content. If you must use JPG, expect some softness on edges.
• You plan to edit it repeatedly. Every lossy save is another round of compression.

Common problems

The converted image looks washed or blocky. Zoom in on the original too; the damage may already be in the WebP. A conversion cannot add detail back.

The file will not load. Check it is within 50 MB and 40 megapixels, and reduce the dimensions in an editor if not.

I have a whole folder. The tool does one image at a time, so it is not built for bulk work.

Related reading

What is WebP? covers the format itself, and WebP vs JPEG compares the two. For the general lossless-versus-lossy question, see PNG vs JPG.

Convert it now: WebP to JPG.

Frequently asked questions

Related tools

More guides

Sources

Plain-text references. Facts that could not be checked against a primary source were left out.

1. MDN Web Docs, 'Image file type and format guide', https://developer.mozilla.org/en-US/docs/Web/Media/Guides/Formats/Image_types
2. Google, 'WebP Frequently Asked Questions', https://developers.google.com/speed/webp/faq
3. MDN Web Docs, 'HTMLCanvasElement: toBlob() method', https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/toBlob