What a WebP file is
What a .WEBP file is, what it does well, what opens one, and how to convert it — with every conversion running in your own browser.
What a WebP file is
A WebP is an image format that can do almost everything the older ones do individually. It compresses photographs with loss like JPG, stores flat graphics without loss like PNG, keeps a full alpha channel, and holds animation frames like GIF — all in one container.
In practice it is used mainly for the first of those. A photograph saved as WebP is typically a quarter to a third smaller than the equivalent JPG at matching visible quality, which on an image-heavy page is a real difference in how fast it loads.
It is a web format in the literal sense: browsers read it universally, and a great deal of desktop software still does not. That asymmetry is what most WebP questions come down to — the file downloaded from a website, and then nothing on the computer would open it.
Where it came from
Google published WebP in 2010, built on the still-frame compression from its VP8 video codec. Adoption was slow for years because Safari held out; it landed there in 2020, and WebP went from a Chrome curiosity to something every browser reads within a single release cycle.
WebP at a glance
| Property | WebP |
|---|---|
| Compression | Lossless or lossy |
| Colour | 8 bits per channel |
| Transparency | Full alpha channel |
| Animation | Yes |
| Keeps EXIF | Yes |
| Browser support | Chrome 32, Firefox 65, Safari 14 |
| Size of a photograph | 25 to 35 percent smaller than a JPG |
| Published | 2010 |
WebP at a glance
- The format supports both lossy and lossless compression, and a file does not announce which it used in a way most viewers show. This site's encoder writes the lossy kind.
- Colour is stored as 8 bits per channel, which is enough for the gradients in a photograph to look smooth rather than stepped.
- Transparency is a full alpha channel: each pixel records how transparent it is, so a soft edge stays soft against any background.
- The container holds more than one frame, so converting to a still format keeps the first and discards the rest.
- Camera settings, dates, and copyright fields travel with the image, which matters if you are converting photographs you intend to keep attribution for.
What it is good at
- Full transparency: each pixel records how transparent it is, so edges blend cleanly into any background.
- Holds several frames and plays them, so it can carry a short looping clip.
- Compresses either way: with loss for photographs, without it for flat graphics, in the same format.
- Carries camera settings, dates, and copyright information alongside the image.
- Roughly 25 to 35 per cent smaller than a JPG of the same photograph at matching visible quality.
Where it falls short
- Read only by newer browsers: Chrome 32, Firefox 65, Safari 14.
What to use instead of WebP
- For an image that has to display everywhere without a fallback, use PNG or JPG. Both have been read by every browser for longer than most of the alternatives have existed.
When to use WebP
Choose WebP for images on a website you control, where the browser is what has to read the file. It is meaningfully smaller than JPG for photographs and than PNG for graphics, it keeps transparency properly, and every browser in use reads it.
Avoid WebP for a file you are sending to somebody else, unless you know what they will open it with. Browser support is universal and desktop support is not, and a WebP that a recipient's photo software refuses is a file you will have to convert and send again.
What opens a WebP file
On a computer, WebP files open in GIMP, Photoshop 23 and later, recent versions of Preview.
Browser support is more recent: Chrome 32, Firefox 65, Safari 14. An older browser will offer to download the file rather than show it.
Turn a WebP file into something else:
Produce a WebP file from something else:
Common problems with WebP
- Only the first frame came out.
- The format you converted to holds one image, so there was nowhere for the remaining frames to go. Convert to animated WebP if the movement matters. It stores the same animation in a fraction of the size, with full colour and proper transparency.
- It displays for me and not for some visitors.
- Support for this format arrived relatively recently, so an older browser or an out-of-date device may not read it. Serve an older format alongside it and let the browser choose, or convert to PNG or JPG if you cannot control the markup.
Converting a WebP file here
- Choose your file, or drag it onto the box. It is read from your device and goes no further.
- Set whatever the conversion offers — quality, size, background — and start it. Everything runs on your own machine, so a large image uses your memory and your processor rather than a queue somewhere.
- Download the result. Nothing is kept: leaving the page or resetting it releases the file and the converted copy alike.
WebP against the alternatives
Common questions
- Why will nothing on my computer open a WebP?
- Because browser support and desktop support are separate things and moved at different speeds. Every current browser reads WebP; a good deal of older photo software, and some printing and publishing tools, never added it. Converting to PNG or JPG is the usual fix, and which one depends on whether the image needs transparency.
- Is WebP lossy or lossless?
- Either — it supports both modes, and the file does not announce which it used in a way most viewers show. This site's encoder writes lossy WebP, which is what the format is overwhelmingly used for and where its size advantage lies.
- Does converting to WebP lose quality?
- The lossy mode does, in the same way JPG does, though it generally holds up better at the same file size. Converting a JPG to WebP re-encodes an image that has already lost detail, so choose the higher quality setting rather than matching the source's size.
- Is transparency kept when I convert a WebP file?
- Only if the format you convert to has somewhere to put it. PNG, WebP, AVIF, and GIF all do, to varying degrees; JPG and BMP do not, and a transparent area becomes a solid colour when you convert to one. The tool tells you which background it used.
- Do all the frames survive a conversion?
- Only when the target format animates too. Converting to a still format keeps the first frame and drops the rest, which is usually not what somebody wants and is easy to do by accident. Animated WebP is the format to convert to if the movement matters.
- What happens to the camera data and copyright fields?
- They survive where the target format has somewhere to keep them and are dropped where it does not. If attribution matters, check the result rather than assume — metadata is the first thing most conversions lose, and it goes silently.
- How much smaller or larger will the file get?
- The table above states the size of the same photograph in each format against JPG, which is the closest thing to an answer that holds in general. The real figure depends on the picture: flat colour and sharp edges behave very differently from a photograph, and the ranges assume a photograph.
- How do I open a .WEBP file?
- The software listed above reads them directly. If nothing on your machine will, converting to PNG or JPG is the reliable route — both open in everything, and the conversion happens here in your browser rather than on a server.
- Does converting a WebP file lose quality?
- It depends on what you convert it to rather than on what you convert from. Converting to a lossless format such as PNG preserves every pixel; converting to JPG, WebP, or AVIF discards detail permanently. Nothing recovers quality the file had already lost.
- Is converting from WebP free, and does it upload my file?
- Free, with no account, and nothing is uploaded. Every converter on this site reads your file with the browser's own file APIs, converts it using code running on your device, and hands the result back as a download. You can confirm that yourself in the Network panel of your browser's developer tools.
- Where does the conversion happen?
- In your browser, on your own device. There is no conversion server here to upload anything to, and no third-party service is involved. That is a statement about what the site does rather than a promise about how it handles uploads, because no upload takes place.