WebP vs PNG
WebP vs PNG: smaller files vs universal support, and when lossless WebP is worth the compatibility tradeoff.
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The short answer
WebP produces meaningfully smaller files than PNG at equivalent quality, in both lossy and lossless modes, and every browser still in meaningful use supports it — so for web images it's the better default. PNG stays the safer choice for images that travel outside the browser: design files, print pipelines, or any app you don't control that might not read WebP.
| Dimension | WebP | PNG |
|---|---|---|
| File size | 20-30% smaller at same quality | Larger, especially lossless |
| Transparency | Alpha channel supported | Alpha channel supported |
| Animation | Supported (replaces animated GIF) | Not supported |
| Lossy mode | Available, smaller than JPEG too | Lossless only |
| Compatibility | All modern browsers; older tools may choke | Universal, decades of support |
Choose WebP when
- →You're serving images to a browser and want smaller payloads without a visible quality hit — the default case for most sites now.
- →You need transparency AND smaller file size at once; WebP beats PNG at both lossy and lossless compression.
- →You have simple animations and want to drop animated GIF's huge file size and limited color palette.
Choose PNG when
- →The file needs to open reliably outside a browser — design tools, older image editors, print workflows, email clients.
- →You're generating assets programmatically (screenshots, charts, favicons) for pipelines that expect PNG specifically.
- →Pixel-perfect lossless output matters and you can't risk a downstream tool mishandling WebP.
The catch nobody mentions
'WebP is smaller' assumes you're comparing against an unoptimized PNG — a PNG properly run through a modern optimizer (pngquant, oxipng) closes much of the gap, and for images with large flat color areas the difference can be small. Benchmark your actual images before assuming the swap saves as much as the marketing claims.