PNG files are larger than they need to be for most web use. WebP delivers the same image at 25-34% smaller file sizes — Google's own benchmark from the format's launch. For a site with dozens of images, that difference adds up to faster load times and lower bandwidth costs.
Why WebP reduces file size without quality loss
WebP uses a more efficient compression algorithm than PNG. PNG's compression is lossless — it stores every pixel exactly. WebP can also be lossless, but its lossless mode still produces smaller files than PNG because the algorithm is newer and more efficient. In lossy mode, WebP's savings are even larger.
Google developed WebP in 2010 specifically to replace PNG and JPG on the web. All major browsers have supported it since 2020. If you're serving images on a website, WebP is the right format — not PNG.
PNG vs WebP: when each format wins
WebP wins for web delivery: smaller files, full transparency support, broad browser compatibility. Use it for website images, blog post graphics, app UI assets, and anything that loads in a browser.
PNG still wins for print workflows and design tool compatibility. Some design software (older versions of Photoshop, certain print production tools) doesn't import WebP. If you're sending files to a printer or to a designer working in an older toolchain, PNG is safer. PNG is also the better archival format — lossless by definition, no quality degradation over repeated saves.
How to convert PNG to WebP
Open the PNG to WebP converter. Upload your PNG file by clicking the upload button or dragging the file onto the page. Choose lossy or lossless output and set your quality level if using lossy compression.
Click convert, then download the .webp file. The filename stays the same — only the extension changes. Processing happens server-side, so there's nothing to install and no file size limit beyond the 20 MB upload cap.
Transparency and alpha channel
WebP fully supports alpha transparency. If your PNG has a transparent background — a logo, an icon, a product cutout — the transparency transfers to WebP exactly. You don't need to flatten the image or add a white background first.
This is a key advantage over converting to JPG. JPG cannot store transparency at all; converting a transparent PNG to JPG forces a white or colored background. WebP preserves the alpha channel, making it the correct format for transparent images on the web.
Choosing a quality level
For lossy WebP, quality 80-85 is the standard starting point for web images. At quality 80, file sizes are typically 50-70% smaller than the equivalent PNG while remaining visually identical on screen. Quality 90+ is appropriate for images that will be displayed large or where subtle detail matters.
If your PNG contains text, sharp lines, or pixel art, use lossless WebP instead of lossy. Lossy compression introduces artifacts at hard edges and text, which lossless avoids entirely. Lossless WebP is still 20-30% smaller than the equivalent PNG. You can also start from a JPG — the JPG to WebP converter works the same way. For further size reduction after conversion, run the output through the image compressor.
When to convert and when to keep PNG
Convert PNG to WebP whenever the image is going on a website. Keep PNG when you're handing files to designers, sending to print, or archiving originals. For transparency on the web, WebP is the right choice — smaller than PNG, and unlike JPG, the alpha channel stays intact.