PNG is the go-to format for logos, icons, screenshots and any image with a transparent background. Its weakness is size. Large PNGs, especially photographs saved as PNG, can slow a website noticeably. WebP solves this neatly: it supports the same smooth transparency as PNG, but usually in a much smaller file. This guide explains how to get the most out of the PNG to WebP converter.
Two kinds of WebP
WebP can work in two different ways, and choosing the right one is the key to a good result.
Lossless WebP
Lossless WebP keeps every pixel exactly the same, just like PNG, but compresses more efficiently. For screenshots, logos, icons, diagrams and illustrations, lossless WebP is commonly around a quarter smaller than an optimised PNG, with no change at all in appearance.
Lossy WebP
Lossy WebP approximates the image, discarding detail people rarely notice. For photographs saved as PNG, lossy WebP can be dramatically smaller, often a small fraction of the PNG size. Transparency is still supported in lossy mode.
Which should you choose?
- Logos, icons, text, screenshots, charts and line art: switch Lossless on. You keep perfectly sharp edges and still save space.
- Photographs and images with lots of texture: leave lossless off and use a quality between 75 and 85.
- Not sure? Try both and compare the file sizes shown on the result page. Converting twice takes seconds.
Transparency is preserved
Unlike JPG, WebP supports transparency in both lossless and lossy modes, including semi-transparent pixels such as soft shadows and anti-aliased edges. Your logo will sit on any background exactly as it did as a PNG.
Step by step
- Open the PNG to WebP tool.
- Choose your PNG or drag it onto the page. The page checks the file and tells you whether it has transparency.
- Decide on Lossless for graphics, or a Quality value for photos.
- Press Convert to WebP.
- Compare the new size on the result page, then download.
Where WebP works today
All current major browsers display WebP, so it is safe for websites. Many modern apps and design tools also support it. If you need to send an image to someone using older software, keep a PNG copy as well. WebP is primarily a web delivery format, while PNG remains a universal working format.
Tips for web performance
Resize before converting
A 3,000 pixel wide logo displayed at 300 pixels wastes bandwidth regardless of format. Export at the size you need, then convert.
Use lossless for user interface graphics
Buttons, icons and interface elements look best with lossless compression, where every edge stays sharp.
Use lossy for decorative photos
Hero images, backgrounds and product photos with transparent cut-outs can use lossy WebP with transparency for big savings.
Test on a real page
Load your page with the new images on a phone over mobile data. The difference in loading speed is often immediately obvious.
Colour and metadata
Colour profiles embedded in your PNG are kept so colours look the same. Hidden metadata from editing software is not copied, which keeps files lean and avoids leaking information you did not mean to share.
Limits
The tool page lists file size and dimension limits. Most graphics and screenshots are well within them. Very large images receive a clear message before any conversion begins.
Privacy
Your images are processed privately and are not published or shared. Download links are personal and expire quickly. Uploaded and converted files are deleted automatically after a short retention period, and guest files are removed shortly after download.
Frequently asked questions
Will lossless WebP look different from my PNG? No. Lossless means every pixel is identical.
Why did my WebP come out larger than the PNG? This occasionally happens with tiny or already highly optimised graphics. Try lossy mode, or keep the PNG if it is already small.
Is transparency supported in lossy mode? Yes. WebP supports transparency in both modes.
Can I convert WebP back to PNG? Yes, with WebP to PNG. If you used lossless, the result is identical to your original.
A worked example: a documentation site
Suppose you write online help pages full of screenshots. Each screenshot is a PNG of around 400 KB, and a typical page has fifteen of them, so every visit downloads around 6 MB of images. Here is a simple improvement:
- Convert each screenshot with Lossless switched on.
- Check one or two results at full size. Every letter and line is identical to the PNG.
- Replace the images on your pages.
Lossless WebP alone usually trims a noticeable amount. If you also crop screenshots to the part of the screen that matters, the total for each page can drop much further. Readers on slow connections reach the useful part of the page sooner.
Now suppose the same site has a few large decorative photos saved as PNG, such as a team picture on the About page. Those benefit from the lossy setting. A 6 MB PNG photo at quality 80 typically becomes a few hundred kilobytes, and visitors will not see a difference.
Understanding the size numbers
The result page shows the size of your new file. If you are converting many images, keep a rough note of before and after sizes. It helps you decide which settings work best for your kind of images, and it is satisfying to see how much faster your pages become.
Common mistakes
- Using lossy mode for text-heavy images. Lossy compression can soften text. Use lossless for screenshots.
- Converting images that are already tiny. A 3 KB icon will not get meaningfully smaller.
- Forgetting older software. Keep PNG copies for colleagues who need to edit the images in older programs.
- Never checking on a phone. Always look at a converted page on a real mobile device.
In short
PNG to WebP is one of the most effective ways to speed up a website that relies on graphics with transparent backgrounds. Choose lossless for logos, icons and screenshots, lossy for photographs, and always resize to the display size first. Keep your PNG originals for editing and sharing with older software, and serve WebP to your visitors.