What Is WebP? Google's Image Format That Speeds Up the Web
You saved an image from your browser — and the file ends in .webp, which your old editor flatly refuses to open. It's not a bug or a virus: that's what a modern format from Google looks like, quietly powering millions of fast websites. Let's unpack what this thing is, why it's lighter than JPEG and PNG, and whether you should worry about it at all.
What WebP is in plain English
WebP (pronounced "weppy") is an image format Google built specifically for the web. Its goal is very concrete: show the same picture as a regular JPEG or PNG, but in a smaller file. Smaller file means a faster page, less data used, and a better spot in search rankings. Files in this format carry the .webp extension.
The clever part is that WebP combines the strengths of three older formats at once. It can compress photos with loss, like JPEG; store graphics and transparency without loss, like PNG; and play animation, like GIF. In effect it's "three formats in one" — and it's almost always lighter than any of them.
In short
WebP is Google's all-purpose image format for the web. It replaces JPEG, PNG and GIF, delivers the same quality in a smaller file, and works in almost every modern browser.
Who created WebP, and why
WebP was introduced by Google on September 30, 2010. The reason was purely practical: the web kept growing, page images kept getting heavier, and images are usually the single bulkiest part of any website. Google — which cares deeply about a fast web — decided to offer a format that squeezes images harder than JPEG with no visible loss of quality.
This wasn't built from thin air. Shortly before, Google had bought On2 Technologies, a maker of video codecs. WebP's compression grew out of their VP8 codec: the format literally reuses the same tricks video uses to compress individual frames. That's the key reason WebP is so compact — more on that below.
Two compression modes: lossy and lossless
WebP's main strength is that it isn't tied to one compression method — it works in two modes. Think of it as two tools in one body: grab whichever the job needs.
Lossy compression is built on the VP8 codec. It works much like JPEG: the tiniest details your eye won't notice anyway are dropped for a smaller size. But WebP does it more cleverly — it predicts the color of nearby pixels from ones already processed, exactly the way a video codec predicts a frame from the previous one. This is the ideal mode for photographs.
Lossless compression uses a separate codec, VP8L. Here not a single pixel is lost: the format spots image fragments it has already seen and reuses them instead of storing them again. This mode is made for logos, icons, screenshots, diagrams and any graphics with crisp edges, where every dot matters.
How to choose a mode
For photos, use lossy WebP — it gives the smallest file. For logos, screenshots and graphics with sharp lines, choose lossless so text and edges stay perfectly crisp.
Transparency and animation in one format
Web designers used to juggle formats: need transparency, reach for PNG; need animation, reach for GIF; need a light photo, reach for JPEG. WebP removes that headache because it does it all.
Transparency. WebP supports an alpha channel — semi-transparent pixels and smooth shadows — and it does so in both compression modes. That's a real advantage: PNG has transparency but is heavy; JPEG has no transparency at all. WebP gives you both — a transparent background in a small file.
Animation. WebP can store a sequence of frames, which makes it a drop-in replacement for the animated GIF. And the difference is huge: where an old GIF is limited to 256 colors and weighs several megabytes, an animated WebP shows a full-color picture in a fraction of the size. That's exactly why so many sites have quietly moved their "GIFs" to WebP.
.webp file.Technically all of this rides on the RIFF container — a simple structure that holds the VP8 or VP8L codec data plus the extras: alpha channel, animation frames, color profile. The maximum size of a single image is a generous 16,383×16,383 pixels, so resolution is never the limit.
How much smaller WebP is than JPEG and PNG
Now for the part the format was created for — the numbers. These aren't marketing promises but Google's own figures:
What does that mean in practice? A photo that weighs 200 KB as a JPEG becomes roughly 130–150 KB as WebP at the same quality. A 100 KB PNG logo drops to around 74 KB as lossless WebP. When a page has dozens of such images, the savings add up to hundreds of kilobytes and noticeably speed up loading — especially on mobile connections.
| Capability | WebP | JPEG | PNG |
|---|---|---|---|
| Lossy compression | Yes | Yes | No |
| Lossless compression | Yes | No | Yes |
| Transparency (alpha) | Yes | No | Yes |
| Animation | Yes | No | No* |
| File size | Smaller | Medium | Larger |
* Only the separate APNG variant supports animation, not plain PNG.
Browser support and compatibility
For a long time WebP's biggest drawback was weak support: pretty much only Chrome understood it. That problem is now behind us. The format opens in roughly 95–96% of browsers worldwide.
- Chrome, Firefox, Edge, Opera — have supported WebP for years, no settings required.
- Safari — learned to open WebP in version 14 (autumn 2020), so the format works on current iPhones, iPads and Macs.
- Internet Explorer — the one notable holdout, but that browser was retired long ago and is barely used.
Because of this, you can put WebP on a website with confidence. There's just one caveat worth keeping in mind.
Where WebP still trips up
Browsers are fine, but some older programs and image editors still won't open .webp directly. If you need to hand the picture to one of those, just convert it to PNG or JPEG. It's a couple-of-seconds job.
How to open and convert WebP
Good news: to simply view a .webp file you need nothing special. Drag it into any modern browser — Chrome, Firefox, Edge or Safari — and the picture opens. For most cases that's enough.
Trouble starts when you need to edit WebP or upload it to a service that doesn't understand it. Then it's worth converting the format to something more familiar:
Upload the file
Drag your .webp into an online converter — nothing to install.
Pick a format
PNG keeps transparency losslessly; JPEG gives the lightest file for photos.
Download the result
The finished picture opens in any editor: Photoshop, GIMP, Paint or a default viewer.
Open your WebP right now
The free FormatZ converter turns a .webp into a familiar PNG or JPEG in a couple of seconds — right in your browser, with no install and no sign-up.
Need a different result? For photos, WebP to JPG is handier. And if you're building a site and want to move your images to WebP for speed, the reverse conversion comes in: PNG to WebP or JPG to WebP. The full list lives on the all formats page.
