What is WebP? Complete Guide to WebP Image Format

What is WebP?

WebP is an image format developed by Google, first released in 2010. It was designed with a single goal: deliver the same visual quality as JPG and PNG at significantly smaller file sizes.

The format achieves this by using more advanced compression algorithms derived from the VP8 video codec (for lossy compression) and a predictive coding method (for lossless compression). In practice, WebP images are 25-35% smaller than equivalent JPGs and 26% smaller than equivalent PNGs, according to Google's own comparisons.

WebP supports lossy compression, lossless compression, transparency (alpha channel), and animation — making it a genuine all-in-one format that can replace both JPG and PNG in most scenarios.

WebP vs JPG vs PNG: How They Compare

Understanding the differences helps you decide when to use WebP and when to stick with traditional formats.

WebP vs JPG

Both support lossy compression for photographs. At the same visual quality (measured by SSIM or PSNR), WebP files are consistently 25-35% smaller. The quality difference at the same file size is noticeable: WebP preserves more detail around edges and in textured areas where JPG tends to produce blocking artifacts.

WebP also supports lossless mode and transparency, which JPG cannot do at all.

WebP vs PNG

For lossless images with transparency, WebP produces files roughly 26% smaller than PNG. Both are visually identical since both are lossless — the difference is purely in compression efficiency.

WebP's lossless mode is particularly effective for screenshots, UI elements, and graphics with large areas of uniform color.

The trade-off

WebP encoding is slower than JPG encoding (about 5-10x slower at comparable quality settings). For batch processing thousands of images, this can matter. For typical web workflows where you convert images once and serve them many times, the encoding speed is irrelevant — what matters is the delivery size.

Browser Support in 2024

WebP browser support has reached the point where compatibility concerns are largely over:

• Chrome: Supported since version 17 (2012).
• Firefox: Supported since version 65 (2019).
• Safari: Supported since version 14 (2020) on macOS and iOS.
• Edge: Supported since version 18 (2018).
• Opera, Brave, Samsung Internet: All supported.

As of 2024, over 97% of global web users are on browsers that support WebP. The remaining 3% are mostly on Internet Explorer (discontinued by Microsoft) or very old mobile browsers in emerging markets.

For maximum compatibility, serve WebP with a JPG/PNG fallback using the HTML <picture> element:

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

How to Convert Images to WebP

There are several ways to convert your existing images to WebP format:

Online (Fastest)

Use our WebP Converter for quick conversions. Drag and drop your files and download the results. Everything runs in your browser.

Using cwebp (Google's Official Tool)

Google provides a command-line encoder called cwebp:

cwebp -q 80 input.jpg -o output.webp

The -q flag sets quality from 0 to 100. For most web images, 75-85 delivers excellent results.

Using ImageMagick

magick input.jpg -quality 80 output.webp

In Your Build Pipeline

Most modern web frameworks and build tools support automatic WebP conversion:

• Next.js: Built-in Image component automatically serves WebP when the browser supports it.
• Webpack: Use image-webpack-loader or imagemin-webp-webpack-plugin.
• WordPress: Plugins like ShortPixel, Imagify, and EWWW automatically generate WebP versions.
• CDN-level: Cloudflare, AWS CloudFront, and Cloudinary can convert images to WebP on the fly based on the browser's Accept header.

How to Convert WebP Back to JPG or PNG

Sometimes you receive a WebP file and need to convert it to a more traditional format — for uploading to a platform that does not support WebP, inserting into a document, or using in older software.

Our WebP to JPG Converter handles this quickly. You can also use command-line tools:

dwebp input.webp -o output.png

Or with ImageMagick:

magick input.webp output.jpg

Keep in mind that converting a lossy WebP to JPG involves re-encoding, which introduces additional quality loss. If you need the highest quality from a WebP source, convert to PNG (lossless) rather than JPG.

Best Practices for Using WebP on Your Website

If you are adopting WebP for your website, follow these guidelines for the best results:

• Keep your originals. Always store source images in their original format (or as high-quality JPG/PNG). Generate WebP versions from these sources. Never use a WebP file as your only copy.
• Use lossy WebP for photos, lossless for graphics. The same rule as JPG vs PNG applies. Photos compress well with lossy encoding; screenshots, logos, and UI elements should use lossless mode.
• Quality 75-85 for lossy. This range delivers the best balance of visual quality and file size. Going above 90 produces diminishing returns with rapidly increasing file sizes.
• Set proper cache headers. WebP files should have long cache durations (at least 30 days, ideally a year) since they are static assets that rarely change.
• Use responsive images. Combine WebP with srcset to serve appropriately sized images based on the viewport. There is no point serving a 2000px-wide WebP to a phone with a 400px screen.
• Test visual quality. While WebP is generally excellent, certain images (fine text rendered into images, detailed patterns) may show different artifact characteristics than JPG. Always spot-check your converted images.

WebP has matured from an experimental format to a web standard. With near-universal browser support and meaningful size savings, there is no reason not to use it for your web images in 2024. Use our Image Format Converter to start converting your image library today.