Convert PNG to WebP

Why WebP instead of PNG

WebP does something neither PNG nor JPEG manages: it offers both lossless and lossy compression, and it supports an alpha channel in either mode. That means you can keep the transparency that made you choose PNG in the first place while getting file sizes in the range JPEG produces.

For images with transparency the saving is often dramatic — commonly 60 to 80 per cent off a PNG for a logo, an icon set or a product cut-out, with no visible difference. For flat graphics, WebP’s lossless mode still typically beats PNG by 20 to 30 per cent, because it predicts pixels more cleverly before compressing them.

Where WebP is safe to use

Every current browser supports WebP, and has done for years, so for anything displayed on a web page it is a straightforward improvement. It is also handled by most modern design and content tools.

Where it still causes trouble is upload forms and older desktop software. A form that asks for “JPG or PNG” often means it literally and will reject a WebP even though the browser could display it perfectly. Print services and some government systems are the same. If you are converting for a form rather than for a website, check what it accepts first — and if in doubt, PNG or JPEG is the safer choice.

Lossless or lossy

FileBelow encodes WebP in its lossy mode, which is what makes the large savings possible, and picks the quality setting from the size limit you set. If you have not set one, it uses a high quality that is visually indistinguishable from the original for almost all content.

For a logo or icon with large areas of perfectly flat colour, be aware that lossy compression can introduce very faint mottling in those areas. If that matters, set a generous size limit or raise the quality manually in Advanced options — at high settings WebP keeps flat colour clean.