WebP Explained: What It Is, Why It Matters, and When to Use It

WebP is a modern image format developed by Google and released in 2010. It was designed to replace both JPG and PNG on the web by delivering smaller file sizes without a visible reduction in quality. Today, WebP is supported by all major browsers and is one of the most practical format choices for web images.

How WebP Compression Works

WebP uses predictive coding, which means the encoder predicts the value of each pixel based on surrounding pixels and stores only the difference between the prediction and the actual value. This approach, borrowed from video codec technology (specifically the VP8 codec), achieves significantly better compression than the DCT-based algorithm used by JPG.

WebP supports both lossy and lossless compression modes:

• Lossy WebP — Similar to JPG but more efficient. At the same visual quality, a lossy WebP file is typically 25–35 % smaller than an equivalent JPG.
• Lossless WebP — Stores all pixel data without loss. Lossless WebP files are typically 26 % smaller than PNG files of the same image.

WebP also supports an alpha channel (transparency) in both lossy and lossless modes. This gives it an advantage over JPG, which cannot store transparent pixels.

WebP vs JPG: Which Is Smaller?

In most real-world tests on photographic content:

• WebP at 80 % quality produces files that are 25–35 % smaller than JPG at 80 % quality
• The visual difference between the two is imperceptible for most viewers
• Very fine textures (hair, grass, fabric) can occasionally look slightly smoother in WebP

The compression advantage of WebP grows with image resolution. A 4K photograph will typically see a larger percentage reduction when converted to WebP than a small thumbnail image.

WebP vs PNG: Which Should You Choose?

For graphics requiring transparency:

• Lossless WebP is typically 26 % smaller than PNG at the same quality
• Lossy WebP can be dramatically smaller — a logo compressed to lossy WebP at 85 % quality might be 70–80 % smaller than the equivalent PNG, while remaining visually acceptable

The main reason to keep PNG over WebP is legacy compatibility requirements. If you need to support very old browsers (Internet Explorer 11, for example), PNG is the safer choice. For modern audiences, WebP is almost always better.

Browser Support

As of 2025, WebP is supported by:

• Chrome (since version 23, 2012)
• Firefox (since version 65, 2019)
• Safari (since version 14, 2020)
• Edge (Chromium-based, since 2020)
• Opera (full support)
• Android Browser and Chrome for Android (full support)
• Safari on iOS (since iOS 14, 2020)

Global browser support for WebP exceeds 96 % of active browsers. The main gap is Internet Explorer and very old Safari versions, which together account for a very small share of modern web traffic.

When Should You Convert Images to WebP?

Use WebP when:

• You want the smallest file size for website images without visible quality loss
• You need transparency but also want a smaller file than PNG provides
• You control your server and can serve modern formats to modern browsers
• You are optimising for Core Web Vitals and page load speed

Keep JPG or PNG when:

• The recipient's software or platform specifically requires JPG or PNG (some email clients, legacy CMS systems, or print workflows)
• You are archiving originals — use lossless formats (PNG, TIFF) for archival copies
• Your audience includes a significant share of IE11 or iOS 13 users

How to Convert Images to WebP

You can convert JPG and PNG images to WebP directly in your browser:

• Convert JPG to WebP — reduces file size compared to the original JPG
• Convert PNG to WebP — retains transparency while significantly reducing file size
• Image Compressor — compress existing WebP files or convert to WebP with quality control

All conversions happen entirely in your browser. No images are uploaded to any server.

Using WebP on a Website

### Option 1: Serve WebP directly

If your server and users are both modern, simply use `.webp` files as your image source:

```html

<img src="image.webp" alt="Description of the image">

```

### Option 2: Use the `<picture>` element for fallback

For maximum compatibility:

```html

<picture>

<source srcset="image.webp" type="image/webp">

<img src="image.jpg" alt="Description of the image">

</picture>

```

This serves WebP to browsers that support it and falls back to JPG for older browsers.

### Option 3: Use an image CDN

Many modern image CDNs (Cloudflare Images, Imgix, Cloudinary, Next.js Image Optimisation) can automatically convert and serve WebP when the browser supports it, based on the `Accept` header in the HTTP request.

WebP and SEO

Faster pages rank better. Using WebP images reduces page weight, which contributes to faster Largest Contentful Paint (LCP) and a better Core Web Vitals score. Google Search explicitly recommends using modern image formats including WebP as part of its performance guidance.

Using WebP images does not directly affect whether your images appear in Google Image Search — Google indexes all major formats including WebP.

Summary

WebP is a practical, well-supported image format that delivers smaller files than both JPG and PNG at comparable visual quality. If your goal is fast web pages, WebP should be your default choice for any image displayed in a modern browser. Convert your images to WebP using the tools available here — the conversion is fast, free, and completely private.