WebP is the most efficient image format for the web. Converting your PNGs to WebP typically reduces file size by 50–75% with no visible quality difference. Smaller images mean faster websites, lower bandwidth costs, and better Core Web Vitals scores.
Here's how to convert PNG to WebP for free, without uploading your files anywhere.
PNG is a lossless format. It preserves every pixel perfectly, which is why it's used for logos, icons, and graphics with transparency. But PNG files are large — often larger than they need to be for web delivery.
WebP was developed by Google specifically for the web. It supports:
For web use, WebP gives you the best of both worlds: the transparency support of PNG with file sizes closer to JPEG.
WebP is supported by all modern browsers:
If you're building for the web and not supporting extremely old browsers (IE 11, iOS 13 or earlier), WebP is safe to use everywhere.
The conversion runs entirely in your browser using libwebp compiled to WebAssembly. Your PNG is never uploaded to any server.
You can also batch-convert — drop multiple PNG files at once and they all convert to WebP simultaneously.
Lossless WebP — Exactly the same quality as the source PNG, just smaller. Use this for:
Lossy WebP — Significantly smaller files with a small, usually invisible quality reduction. Use this for:
At quality 80–85, lossy WebP files are 60–75% smaller than the equivalent PNG, and visually identical for photographs.
Typical results converting PNG to WebP:
| Source | Method | Savings |
|---|---|---|
| PNG photo → WebP lossy (q80) | ~70% | 4 MB → 1.2 MB |
| PNG graphic → WebP lossless | ~26% | 500 KB → 370 KB |
| PNG with transparency → WebP lossless | ~20–30% | Varies |
Results depend heavily on image content. Photos and gradients compress more than flat-colour graphics.
For web delivery, yes — WebP is almost always a better choice than PNG. The exception is if you need the original to remain lossless for print or professional editing workflows, in which case keep the PNG as your master file and serve WebP on the web.
A common workflow:
AVIF is the next-generation format after WebP, offering even better compression (typically 20–30% smaller than WebP at equivalent quality). However, AVIF encoding is slower and browser support, while growing, is slightly behind WebP.
For most use cases today: WebP is the safe default. AVIF is worth considering if you're serving a large number of images and your audience is on modern browsers.
imgshrnk converts to both WebP and AVIF — choose WebP for compatibility, AVIF for maximum compression.
If you're adding WebP images to an HTML page, use the <picture> element to provide a PNG fallback for older browsers:
<picture>
<source srcset="image.webp" type="image/webp">
<img src="image.png" alt="Description">
</picture>
Modern browsers load the WebP; browsers that don't support it fall back to the PNG.
Most CMS platforms (WordPress with plugins, Shopify, Webflow) handle this automatically if you upload WebP files.