guide

How to Convert PNG to WebP (and When You Should)

· Alex Chen, Image Optimization Engineer

TL;DR

WebP is about 45% smaller than PNG while keeping transparency, and every major browser has supported it for years. For website images, converting PNG to WebP is one of the simplest ways to speed up page loads. echloe converts PNG to WebP in your browser, with no upload and no account.

What is WebP, and why is it smaller than PNG?

WebP is an image format Google built to replace JPEG and PNG on the web. It does both lossy and lossless compression, and it keeps the alpha channel, so a PNG logo with a transparent background stays transparent as a WebP. Google's own measurement puts a WebP at roughly 45% smaller than the equivalent web PNG.

Is WebP safe to use in 2026?

Yes. Browsers covering about 97% of usage support WebP: Chrome and Edge for years, Firefox since 2019, and Safari since 2020. For ordinary website images, the support question is effectively settled.

When should I convert PNG to WebP, and when not?

Convert when the image lives on a web page and file size affects load time. Google's PageSpeed tools explicitly recommend swapping PNG and JPEG for WebP to make pages faster, and on image-heavy pages the savings add up quickly.

Hold off when:

  • The file is going somewhere that expects PNG (some design tools, print workflows, older systems).
  • The image needs 10- or 12-bit color depth. WebP tops out lower, which can show as banding in thin-contrast art or pixel art.

For photos and UI graphics on a site, none of those apply, so WebP is the default choice.

How do I convert a batch of PNGs to WebP?

  • Drop your PNG files into the converter.
  • Choose WebP as the output (lossless if you need a pixel-perfect copy, lossy for the smallest size).
  • Convert and download.

echloe runs the conversion locally with WebAssembly, so your images never upload, and it's free for up to 15 a day. That's enough to convert a site's worth of graphics in a couple of passes.

Key takeaways

  1. WebP is ~45% smaller than PNG and keeps transparency.
  2. About 97% of browsers support WebP, so it is safe for production websites.
  3. Convert for web images to speed up pages; keep PNG for print or 10-bit color work.
  4. Lossless WebP gives a pixel-perfect copy; lossy gives the smallest file.