Convert PNG to WebP
WebP is the safe modern format. It is smaller than PNG, keeps transparency, and opens in things AVIF does not — email clients, older phones, desktop software. If you want one format that works everywhere and is meaningfully smaller than what you started with, this is it.
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Up to 50 MB. Deleted automatically after 30 minutes.
What it does
- No account, deleted within 30 minutes
- Alpha transparency preserved
- Lossless mode available, so pixels stay exact
- Batch conversion with a ZIP download
How to use PNG to WebP
- 1
Add the PNG files
Screenshots, logos, icons, exported graphics, anything with a .png extension. Several at once is fine and they come back as a ZIP.
- 2
Convert
Encoding runs inside this tab using the browser's own WebP encoder, which every current browser reads. The conversion is close to instant even on large files.
- 3
Use it directly
Unlike AVIF, WebP output does not need a fallback in practice. Support reaches back roughly a decade in browsers and covers most desktop software, so you can generally just replace the PNG.
How it works
The browser decodes the PNG, draws it to a canvas, and encodes the result as WebP, on our server.
That is possible here and not on the AVIF pages for a simple reason: browsers ship a WebP encoder and expose it to web pages through the canvas API, but ship only an AVIF decoder. So WebP conversion is local and instant, and AVIF conversion requires a server.
Why PNG is so large
PNG is lossless, which is a genuine virtue and also the whole problem. It reproduces every pixel exactly, and to do that it has to store something about every pixel.
On a screenshot or a logo that is cheap, because the image is full of long runs of identical color that compress to almost nothing. On a photograph it is ruinous: adjacent pixels differ slightly everywhere, sensor noise is real detail as far as the compressor is concerned, and the file balloons. That is the seventeenfold difference in the second example, and it is not WebP being clever so much as PNG being used for something it was never meant to hold.
Lossy or lossless
WebP is two formats sharing one extension, and choosing between them matters more than most people expect.
Lossy uses the same prediction machinery as the VP8 video codec. Use it for photographs and complex images, where it beats JPEG at the same visual quality and the loss is invisible.
Lossless stores exact pixels and still comes out roughly 25 percent below PNG. Use it for screenshots, diagrams, line art, and any image containing text, where lossy compression puts faint rings around sharp edges that are subtle in isolation and obvious once you know to look.
The mistake worth avoiding is running interface screenshots through lossy compression to save a few kilobytes. The text goes slightly soft, and nobody can say why the image looks cheap.
Where WebP fits
Between PNG and AVIF, and the gap it fills is compatibility rather than size.
PNG is universal and large. AVIF is small and only reliably works in browsers. WebP is smaller than PNG, opens almost everywhere, and asks nothing of you in return — no fallback markup, no picture element, no checking what the recipient can read.
For most sites, converting PNGs to WebP captures the large majority of the available saving with none of the complications. AVIF is worth adding afterwards, for the largest images, once the easy win is banked.
Examples
A logo with transparency
About a quarter of the size with the transparency carried across exactly. Flat-color graphics are WebP's strongest case, and this is the conversion most people arrive here for.
A photographic PNG
Seventeen times smaller, because a photograph should never have been a PNG in the first place. PNG is lossless, so it stores photographic noise faithfully and at enormous cost. Any lossy format wins here by a wide margin.
Frequently asked questions
Should I use WebP or AVIF?
WebP when the file has to work outside a browser, or when you want one format and no fallback logic — it opens in email clients, most desktop software, and phones going back years. AVIF when the only consumer is a web page and the byte count genuinely matters, since it is typically another 20 to 30 percent smaller. For most people replacing PNGs on a site, WebP is the pragmatic answer and AVIF is the optimization you do afterwards.
Does this lose quality?
By default yes, at a level you will not see on a photograph but may notice on hard edges and text. WebP also has a lossless mode which stores exact pixels and is still around 25 percent smaller than PNG — worth using for screenshots, diagrams and anything with sharp edges, where lossy compression leaves faint halos.
Is transparency preserved?
Yes, fully. WebP supports an eight-bit alpha channel just as PNG does, so soft shadows and anti-aliased edges survive intact. This is a real advantage over JPEG, which has no transparency at all and is why logos and icons could never move to it.
Will WebP display everywhere?
In browsers, effectively yes — Chrome, Firefox, Safari and Edge have all supported it for years. Outside browsers it is patchier but reasonable: most current desktop software opens it, though some older tools and a few email clients still do not. If a file is going into a document or being handed to someone to edit, PNG remains the safer thing to send.
Further reading
- Cutting a Graphic to Sixteen Colors Saved Fourteen Per CentReducing the palette is standard advice for shrinking a PNG, and on a graphic that is already flat color it buys far less than the drastic-sounding change suggests. The reason is that PNG was already exploiting the same redundancy, and it had got there first.
- GIF Was Perfect on a Page of Text and Ruined the PhotographGIF is usually described as a lossy format, or at least as one that ruins images. That is not quite right. GIF's compression is lossless; what it cannot do is hold more than 256 colors. On an image that already has fewer than that, GIF is perfect. On a photograph it is a disaster. The same format, two completely different outcomes.
- GIF Transparency Has Exactly One Bit, and It Shows on Every EdgeA PNG can record a pixel as 37% transparent. A GIF cannot — each pixel is either fully visible or fully invisible, and there is nothing in between. On a shape with a soft anti-aliased edge, that difference is measurable, and it is why a logo saved as GIF gets a jagged fringe that no amount of care in the original file prevents.