What Is WebP? The Complete Guide to Google's Image Format

WebP is everywhere online — you just might not have noticed it. If you have ever right-clicked an image on Google Search, Pinterest, or a news website and saved it, there is a good chance you ended up with a .webp file. This guide explains what WebP is, why it exists, and what you need to know to work with it.

What Is WebP?

WebP is an image format created by Google and first released in 2010. It was designed to replace JPEG and PNG for web delivery by offering better compression — meaning smaller file sizes — while maintaining equivalent visual quality.

The format is based on the VP8 video codec, which Google open-sourced in 2010 (the same year they released WebP). VP8 was designed for video compression, and the techniques that make video efficient also work well for still images.

WebP supports:

• Lossy compression — like JPEG, with configurable quality
• Lossless compression — like PNG, pixel-perfect
• Transparency (alpha channel) — which JPEG cannot do
• Animation — like animated GIF, but much more efficient

Why Google Created WebP

The web was getting heavier. By 2010, the average web page included multiple large images encoded in JPEG and PNG formats designed in the 1980s and 1990s. Faster page load times directly improve user experience and reduce bounce rates — so Google had a strong incentive to develop a more efficient format.

Google’s initial tests showed WebP achieving:

• ~30% smaller file sizes than JPEG at equivalent quality for lossy images
• ~26% smaller file sizes than PNG for lossless images

For a large website serving millions of images per day, even a 20% size reduction translates to significant bandwidth savings and faster page loads.

WebP vs. JPEG

When WebP wins over JPEG: For web delivery where you control the format. You get smaller files and optionally add transparency — impossible with JPEG.

When JPEG wins: When you need to open or share images in software that does not support WebP, or when interoperability is more important than file size.

WebP vs. PNG

When WebP wins over PNG: Web delivery of lossless images or images with transparency where you want smaller files.

When PNG wins: Editing (round-trips without quality loss), archiving, or compatibility with software that does not support WebP.

WebP vs. AVIF

AVIF (AV1 Image File Format) is a newer format that generally outcompresses WebP. If WebP replaced JPEG and PNG for web delivery, AVIF is the next step:

• AVIF is typically 20–30% smaller than WebP at equivalent quality
• AVIF has HDR and wide color gamut support
• AVIF browser support is now comparable to WebP (Chrome, Firefox, Edge, Safari 16.1+)

For new web projects, AVIF is generally the better choice. WebP remains valuable as a fallback for older browsers.

Browser Support for WebP

WebP is now supported by every major browser:

As of 2025, global WebP support exceeds 97% of all browsers. It is safe to use WebP as your primary format on the web.

Why Can’t I Open WebP Files in Some Programs?

WebP support outside of browsers is still uneven. Common issues:

Windows Photo Viewer (Windows 7/8/10 older versions) — cannot open WebP by default. Windows 11 and Windows 10 (with the latest updates) can open WebP in the Photos app, but not in the legacy Windows Photo Viewer.

Photoshop — older versions require a WebP plugin. Adobe Photoshop CC 2019 and later added native WebP support.

Lightroom Classic — added WebP import support relatively recently. Older versions do not support it.

GIMP — supports WebP natively (versions 2.10+).

macOS Finder / Preview — supports WebP in macOS 12 Monterey and later. Older macOS versions cannot open WebP.

If you encounter a WebP file you cannot open, the simplest solution is to convert it to PNG or JPG — two formats that open everywhere.

How to Convert WebP to Other Formats

WebP to PNG (Lossless)

PNG is the best choice when you need lossless quality, transparency, or an editing-ready format. Convert WebP to PNG →

WebP to JPG (For Sharing)

JPG is smaller than PNG and opens everywhere. Use it when you need to share an image via email or upload it to a platform. Convert WebP to JPG →

Converting with Preview on Mac

1. Open the WebP file in Preview.
2. Go to File → Export.
3. Choose PNG or JPG from the Format dropdown.
4. Click Save.

Converting with Paint on Windows

1. Right-click the WebP → Open with → Paint.
2. File → Save As → PNG or JPEG.

Converting via Command Line

# Using libwebp (dwebp)
dwebp input.webp -o output.png

# Using ImageMagick
convert input.webp output.png

How to Convert Other Formats to WebP

If you want to use WebP on your website, convert your PNG or JPG source files:

• PNG to WebP →
• JPG to WebP →

Tools for batch WebP conversion:

• cwebp (command-line, from Google’s libwebp package)
• Squoosh (Google’s browser-based optimizer)
• Sharp (Node.js library for programmatic conversion)
• ImageMagick (mogrify -format webp *.jpg)

WebP on Your Website: Practical Guide

Serving WebP with a PNG/JPG Fallback

<picture>
  <source srcset="image.webp" type="image/webp">
  <img src="image.png" alt="Description">
</picture>

This serves WebP to browsers that support it and PNG to those that do not.

Checking if a URL Serves WebP

Open Chrome DevTools → Network tab → filter by image. Look at the Type column to see which format was delivered.

Automating WebP Conversion

For production websites, automate the conversion:

• Astro — @astrojs/image automatically generates WebP versions
• Next.js — built-in image optimization serves WebP
• WordPress — plugins like Imagify or Smush convert to WebP automatically
• Cloudflare — Polish feature can automatically convert images to WebP

Is WebP the Right Format for You?

Use WebP when:

• Delivering images on a website (90%+ of users can see it)
• You want smaller files than JPEG with optional transparency
• You are building a modern web application

Use PNG when:

• You need lossless quality for editing or archiving
• You need maximum compatibility across all software
• Images contain text, sharp edges, or screenshots

Use JPEG when:

• Maximum software compatibility is needed
• The image is a photograph with no transparency

Use AVIF when:

• You want the best possible compression for web delivery
• Your target audience has modern browsers (Chrome, Firefox, Edge, Safari 16.1+)

Frequently Asked Questions

Is WebP better than JPEG?

For web delivery, yes — WebP is typically 25–35% smaller at equivalent quality and also supports transparency. For compatibility with desktop software, JPEG still has an advantage due to its universal support.

Does WebP support transparency?

Yes. WebP supports full alpha channel transparency, which JPEG cannot do. This makes WebP useful for logos, icons, and any image with a transparent background.

Is WebP lossless?

WebP supports both lossy and lossless modes. Lossless WebP is pixel-perfect, like PNG. Lossy WebP uses configurable quality levels, like JPEG.

Why do websites serve images as WebP?

To reduce page load times. Smaller images = faster pages = better user experience and potentially better search rankings. Google developed WebP specifically for this purpose.

Will WebP be replaced by AVIF?

Eventually, yes. AVIF generally outcompresses WebP and has comparable browser support as of 2022–2025. For new projects, AVIF is a better long-term choice. WebP will remain relevant as a fallback for years.

How do I convert WebP to PNG?

Use the pixconv.io WebP to PNG converter — it runs in your browser, is free, and requires no account. Alternatively, use Preview on Mac or Paint on Windows.