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🖼️ Image & Photo Tools

Free PNG to WebP Converter with a Live Quality and Size Preview

Drop in PNGs and watch the file size fall as you move the slider — usually by 60 to 80% with no visible difference. Transparency is kept, and nothing is uploaded.

1 — tiny, visibly damaged75–85 — the useful range100
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How the calculation works

Where the quality slider stops paying you back useful range q1018 KB q4042 KB q7588 KB q85126 KB q100340 KB Above about 85 the file grows fast and almost nobody can see the difference. Below 70 the artefacts start to show.

How to Use This Tool

WebP reaches the same visual quality as PNG or JPEG at roughly a third of the size, and every browser released in the last six years supports it. For a page carrying a dozen images that is often the single largest performance win available, and it takes about ten seconds.

Converting

Drop one file or fifty. Each is decoded, redrawn to a canvas and re-encoded as WebP entirely inside your browser — there is no upload, no queue and no size limit beyond your own memory. Move the quality slider and every file re-encodes live, so you can watch the size fall and stop when it starts to look wrong.

Transparency is preserved. A PNG with an alpha channel becomes a WebP with an alpha channel, which is one of the main reasons to choose WebP over JPEG for logos, icons and cut-out product shots.

Choosing a quality setting

Between 75 and 85 is where almost every image should sit. Below about 70 the artefacts become visible on photographs; above 85 the file grows quickly for a difference nobody can see without pixel-peeping. The default of 80 is a good starting point for photographs. For screenshots and flat-colour graphics you can often go lower than you expect, because there is less detail for the encoder to lose.

A typical 1600×1000 screenshot Original PNG 412 KB WebP lossless 279 KB −32%, identical pixels WebP quality 80 89 KB −78%, no visible difference Lossless is worth it for line art and screenshots with text. For photographs it rarely is.
Lossless WebP still beats PNG because it uses a better compression algorithm — you get a third off with genuinely identical pixels, before considering lossy at all.

Lossless mode

Ticking lossless produces a file with pixel-for-pixel identical output, and it still beats PNG by roughly 25 to 35% because WebP's compression is simply better. Use it for line art, diagrams, screenshots containing text, and anything that will be edited again later. For photographs it is rarely worth the size; quality 80 will be four times smaller and indistinguishable.

The skip option

Skip files WebP would make bigger is ticked by default and worth leaving on. Very small images — icons under a couple of kilobytes, simple two-colour PNGs — sometimes come out larger as WebP because the format's header overhead exceeds what it saves. Rather than silently handing you a worse file, the tool flags those and keeps the original.

Where you can safely use the output

WebP works in every version of Chrome, Firefox, Edge and Safari since 2020, which is effectively all real traffic. The remaining gaps are older desktop software rather than browsers: some email clients, some CMS uploaders and a few print workflows still reject it. If a system refuses your file, that is why, and the fix is to keep a JPEG fallback rather than to avoid WebP everywhere.

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Frequently Asked Questions

How much smaller is WebP than PNG?
For photographs, typically 70 to 80% smaller at quality 80 with no visible difference. For screenshots and flat graphics, often more. Even lossless WebP is usually 25 to 35% smaller than the equivalent PNG, because its compression algorithm is simply better than PNG's.
Does WebP support transparency?
Yes, both in lossy and lossless mode, which is the main advantage over JPEG. A transparent PNG converts to a transparent WebP with the alpha channel intact, so logos, icons and cut-out product shots keep their edges.
Is the conversion lossless?
Only if you tick lossless mode. By default the quality slider applies lossy compression, which discards information you generally cannot see. Lossless produces pixel-identical output at a larger size — still smaller than the original PNG, but roughly three times larger than quality 80.
Can every browser display WebP?
Every browser released since 2020, which covers effectively all real traffic including Safari on iOS and macOS. The remaining gaps are non-browser software: some email clients, older CMS uploaders and certain print workflows still reject it. Keep a JPEG fallback for those, not for browsers.
Why did one of my files get skipped?
Because WebP made it larger. Very small or very simple images sometimes come out bigger because the format's fixed overhead exceeds the compression it achieves. Rather than silently giving you a worse file, the tool keeps the original and tells you. You can untick the option to convert anyway.
Are my images uploaded to a server?
No. Every file is decoded and re-encoded by your browser's own canvas, in memory. There is no network request at any point, which is why it works offline and why you can safely convert client work, private photographs or anything under embargo.
What quality setting should I use?
80 is a good default for photographs. The useful range is roughly 75 to 85 — below 70 artefacts become visible, above 85 the file grows quickly for a difference almost nobody can see. Screenshots and flat-colour graphics tolerate lower settings than photographs do.

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