You right-click a picture on a website, save it, and the file ends in .webp. Then the program
you wanted to use won't open it, or an upload form rejects it. If that's how you ended up here, the short
answer is that WebP is a perfectly normal image format with one weakness, compatibility, and it's easy
to convert when you need to.
What WebP is
WebP is an image format Google released in 2010 to make web pages load faster. It does the jobs of both older formats in one:
- Lossy mode compresses photos the way JPG does, but more efficiently.
- Lossless mode keeps every pixel exact, like PNG, usually in a smaller file.
- Both modes support transparent backgrounds, which JPG can't do.
- It also supports animation, as a far smaller replacement for GIF.
How much smaller? We measured it. A 2560 × 1600 photo saved as WebP was 18% smaller than the same photo as JPG at the same quality setting, and it came out slightly closer to the original. A screenshot of a document saved as lossless WebP was 24 KB, against 72 KB as PNG, pixel-for-pixel identical at a third of the size. The full comparison is in our JPG vs PNG vs WebP guide.
Why images save as WebP
Because that's what the website sent. Faster pages rank better and cost less to serve, so most large sites now deliver WebP to any browser that supports it, which today means all of them. When you choose “Save image as”, your browser simply saves the file it received.
Some sites go further and choose the format per visitor: the same image link can arrive as WebP in Chrome and as JPG in an older app. That's why a picture can seem to “change format” depending on where you open it.
Where it opens, and where it doesn't
Works: every current web browser (Chrome, Edge, Firefox, Safari since 2020), the Photos app on Windows 11, Preview on recent versions of macOS, and iPhones and Android phones.
Can cause trouble:
- Upload forms that accept only JPG and PNG. Many government, university and job portals are in this group.
- Older versions of image editors and office software. Photoshop, for example, only gained built-in WebP support in 2022.
- Print shops and photo kiosks, which usually expect JPG.
- Older Windows setups. If WebP files won't open there, Microsoft's free “WebP Image Extensions” in the Microsoft Store adds support.
Converting WebP to JPG or PNG
First decide which one you need:
- JPG for photographs. It's smallest, and accepted everywhere.
- PNG for logos, icons, screenshots, or anything with a transparent background. JPG would fill the transparent areas with a solid colour.
Both conversions run in your browser here, so the image isn't uploaded anywhere:
PNG to JPG Pick a background colour and quality level before converting.
JPG to PNG A fast, lossless conversion at full resolution.
Despite their names, both tools accept WebP files. On a Mac, Preview can also do it: open the file, choose File → Export, and pick JPEG or PNG.
Changing photo.webp to photo.jpg only changes the label. The contents are still
WebP, and a strict program or upload form will reject it or show an error, sometimes one that's harder to
understand than the original problem. Convert it properly instead.
Does converting affect quality?
Converting to PNG keeps the image exactly as it is. The file will be bigger, but nothing changes visually. Converting to JPG adds one more round of compression. At quality 85–90 the difference won't be visible, but avoid converting the same image back and forth repeatedly; every lossy save costs a little detail.
Neither conversion can improve the image. If the WebP was heavily compressed, its flaws come along into the new file.
Should you use WebP yourself?
- On your own website: yes. Smaller images mean faster pages, and every browser your visitors use supports it. Our image compressor can output WebP directly.
- For sending to people or uploading to forms: stick with JPG for photos and PNG for graphics. The few kilobytes saved aren't worth a rejected upload or a confused recipient.
Image Compressor Make the file smaller without making the picture worse.