When building a website, PNG has traditionally been the go-to format for logos, icons, and any image requiring a transparent background. But WebP has changed the rules.

While WebP is famous for replacing JPGs with its lossy compression, its lossless compression mode makes it a direct, and often superior, competitor to PNG.

The Core Difference

Both PNG and WebP support lossless compression and alpha transparency (transparent backgrounds). The difference lies entirely in the efficiency of the compression algorithm.

Google's WebP algorithm is simply much better at packing the exact same pixel data into a smaller file.

File Size Savings

According to Google's data, lossless WebP images are, on average, 26% smaller than equivalent PNGs.

This means you can take a 100 KB transparent PNG logo, convert it to a lossless WebP, and get a 74 KB file that looks completely identical on screen. For websites loading dozens of icons and graphics, these savings stack up quickly.

When WebP Can Replace PNG

You should replace PNG with WebP when the image is intended for viewing on a modern web browser or mobile app.

  • Website Logos: Huge impact on first-load performance.
  • UI Icons: Small file sizes make UI assets load instantly.
  • Screenshots on Blogs: WebP keeps text sharp (unlike JPG) but at a smaller size than PNG.
  • Transparent Product Images: Essential for e-commerce sites showing products on dynamic backgrounds.

When to Stick with PNG

WebP is primarily a delivery format (for serving to end-users), while PNG remains a strong authoring and archival format. Stick to PNG when:

  1. You are editing the image: Not all design software handles WebP seamlessly. If an image is a "work in progress" moving between Photoshop, Illustrator, and other tools, keep it as a PNG.
  2. You are sharing raw assets: If you are sending a logo to a print shop or a client who might not know what a WebP file is, send a PNG. It is universally compatible.
  3. Email Signatures: Email clients (like older versions of Outlook) have notoriously bad support for modern web standards. Use PNG for logos in email signatures to ensure they display for everyone.

Converting PNG to WebP

If you have a library of PNG assets for your website, converting them to WebP is a quick win for performance.

  1. Go to ToolzStack's Image Converter.
  2. Upload your PNG file.
  3. Select WebP as the output format.
  4. Download your new WebP image and replace the PNG on your site.

Note: Ensure you are using lossless WebP conversion if you want to perfectly preserve the sharp edges of logos or text.

Related guides: JPG vs PNG · JPG vs WebP