More about converting PNG to WebP
WebP is Google's modern image format designed to replace both JPG and PNG on the web, supported natively by Chrome since 2010, Firefox since 2019, Safari since macOS Big Sur and iOS 14, and Edge since 2018. Converting PNG to WebP delivers 20-30% smaller files at lossless quality and up to 70% smaller at high lossy quality, with full alpha-channel support intact. For static site generators (Hugo, Eleventy, Astro), Next.js Image, and Cloudflare's Polish pipeline, WebP is now the default delivery format for transparent assets.
WebP supports both lossless and lossy encoding modes - lossless uses a predictive transform plus entropy coding similar to PNG's DEFLATE but smarter, while lossy uses VP8-derived block prediction like a single video keyframe. For UI assets, icons, and screenshots stick with lossless WebP to preserve crisp pixel edges; for photographic content with transparency (product shots on white, hero images with vignettes) lossy WebP at quality 80-85 is visually indistinguishable from the source PNG and 60-75% smaller. Alpha is preserved in both modes.
The main reason teams still ship PNG fallbacks is legacy browser support - IE11, older Safari, and ancient Android WebViews don't recognize the format. The standard approach is the HTML5 picture element with WebP source and PNG fallback, or content negotiation via Accept headers in Cloudflare Workers / Vercel Edge. For app icons (iOS, Android, Windows), favicons, and email signatures, keep PNG. For everything served from a website CDN, convert to WebP. See also JPG to WebP for photographic sources.
When you'd use this
Reasons to convert PNG to WebP usually come down to compatibility, file-size, or specific feature requirements. Common situations:
- An app or platform only accepts WebP uploads.
- You need a feature unique to WebP (e.g. transparency, vector scaling, animation, multi-page pages, etc.) that PNG doesn't provide.
- You're optimising file size — modern formats often produce smaller files than the older format you started with.
- You need a single archival format across a project so files behave consistently in the same viewer.
How to do it in jpg.now
- Open the PNG → WebP tool on jpg.now.
- Drag your PNG file onto the drop zone, or click Select files. You can drop a whole folder of files at once.
- The output is fixed to WebP. If the format supports extra options (page size, transparency background, quality, EXIF stripping), tweak them in the right-hand panel.
- Click Convert. The job runs on our server and finishes in a few seconds for typical photos.
- Download the result. Files stay in storage for 24 hours and are then permanently deleted.
The entire flow is free for the first 10 jobs per day with no signup required. A free account doubles that quota; a premium plan removes the limit entirely.
Tips and common pitfalls
- Use lossless WebP for screenshots, UI mockups, and any image with sharp text - it's 20-30% smaller than optimized PNG with bit-perfect fidelity.
- Use lossy WebP at quality 80-85 for photographic content with transparency - product shots and hero images shrink 60-75% with no visible difference.
- Always ship a PNG fallback via the picture element if you support legacy browsers - or use a CDN that does Accept-header negotiation automatically.
- Don't convert iOS or Android app icons to WebP - the asset catalogs still require PNG at fixed pixel sizes (180x180, 192x192, etc).
- Strip the EXIF and color profile chunks with cwebp -metadata none for the smallest possible output - they're rarely needed on web assets.