Disclosure: Save Image As Type is ours, and this blog is published by the same people. Anything said here about our own software is written by an interested party. One of the routes below is our own extension. The other routes are here because they are genuinely better in some situations, and each says when.
Why are images saved as WebP?
WebP is an image format Google developed to make web pages smaller. Google’s own figures put WebP lossy images at 25-34% smaller than comparable JPEG at an equivalent SSIM quality index, which is why so many sites now serve it.[1] The saving is real. The problem is that the file then has to leave the browser, and plenty of software outside the browser still will not open it.
You never chose the format either: your browser advertises WebP support on every image request and the site’s image server answers accordingly. The WebP problem, end to end covers why the file arrived as a WebP, why your desktop cannot open it, and all five routes out of it. This article is the one route in detail.
Common reasons to convert a WebP to JPG:
- Sending it to someone, where JPG opens on anything
- Opening it in older image editors that never added WebP support
- Uploading it somewhere that rejects the file type
- Print services, which usually want JPG or PNG
Method 1: convert it with a browser extension
The fastest route is an extension that adds format options to the right-click menu, so the file is converted before it is written to disk. Several do this and we compare four of them, including ours. With Save Image As Type the steps are:
- Install the extension for Chrome, Firefox or Edge
- Right-click the WebP image
- Choose Save Image As Type, then Save as JPG
The conversion runs in the browser using the Canvas API, so the image is not uploaded anywhere. JPG output is encoded at 95% quality by default and the level is adjustable in Settings.
What it costs you: JPG is a lossy format. The image is re-encoded, not repackaged. At 95% the difference is not visible at normal viewing size, but it is not a byte-for-byte copy and it never can be. If you need the pixels preserved exactly, save it as PNG instead - PNG is lossless and the file will be larger.
What else changes when the output is JPG
Two things happen quietly, and both are the format rather than the tool.
A transparent background turns white. WebP has an alpha channel and JPG has none, so transparency cannot survive the conversion - something has to be put behind the image. Save Image As Type fills the canvas with white before drawing, so a logo with a transparent background comes out as that logo on a white rectangle. On a white page you will not notice. On anything else you will, and no converter can avoid it, because the format has nowhere to put an alpha channel. If the transparency matters, save it as PNG, which keeps it.
An animated WebP comes out as one frame. WebP can hold animation and JPG cannot, so the output is the first frame and the rest is discarded. Same for animated GIFs. A JPG holds one image by definition.
Method 2: can you just rename the file extension?
No. Renaming photo.webp to photo.jpg changes the filename and nothing else.
The bytes inside are still WebP, so software that could not open the WebP still
cannot open it, and now the error message is confusing because the extension lies
about the contents.
This is worth stating plainly because it is the most common advice on the topic and it does not work.
Method 3: upload it to an online converter
Sites like CloudConvert, Convertio and Zamzar will convert the file after you upload it. The result is a genuine JPG.
What it costs you: the image goes to a server you do not control. If it is a screenshot of anything private, that is a decision, not a detail. Free tiers are also metered - CloudConvert’s free plan allows 10 conversion credits a day - and the whole process takes an upload and a download where a right-click would have done.[2]
They are genuinely the right answer in one case: a file already sitting on your disk. A browser extension converts what is in a web page, so it cannot help with a WebP somebody emailed you. On Windows there is a route out of that case that needs no upload at all - the file will not open because Windows is missing one free codec, and once it is installed Paint converts the file locally.
Which method should you use?
| Method | Real conversion | Image stays on your device | Steps |
|---|---|---|---|
| Browser extension | Yes | Yes | One right-click |
| Renaming the file | No | Yes | Does not work |
| Online converter | Yes | No | Upload, convert, download |
Every method that produces a real JPG loses transparency and animation, because that is the format doing it, not the tool. An online converter will flatten a transparent background exactly the same way.
For an image on a page you are looking at, the extension. For a file already on disk, an online converter or a desktop image editor.
Should you keep the WebP as well?
If the image is going back onto a website, yes - that is the case WebP is good at, and converting to JPG throws away the size advantage the format exists for. Keep the WebP for the web and make a JPG for the thing that cannot read it.
Save Image As Type also outputs PNG, AVIF and PDF, so the same right-click covers the case where JPG is not what you needed after all.
Sources
- Google: WebP compression study and format overviewPrimary source
That WebP lossy images are 25-34% smaller than comparable JPEG images at an equivalent SSIM quality index.
- CloudConvert pricingPrimary source
That CloudConvert's free plan is metered at 10 conversion credits per day. Read .
