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PNG to WebP Converter

Convert .png to .webp for smaller files at the same visual quality, with transparency preserved. Runs entirely in your browser.

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What is WebP and why does it matter?

WebP is an image format developed by Google in 2010 to give the web a single, modern container that does what JPG and PNG each do separately, but better. It supports both lossy and lossless compression, encodes alpha transparency natively, and on average produces files 25–35% smaller than JPG and PNG at the same perceived quality.

For a portfolio site, an e-commerce product gallery, or any content where image weight drives load time, converting PNGs to WebP is the simplest performance win available. Page weight drops, Largest Contentful Paint improves, and the green-circle Core Web Vitals score gets easier to hit without any other changes.

How this converter is configured

We convert to lossy WebP at quality 0.9, which sits in the sweet spot of "visually identical to the PNG" for almost every input — photographs, screenshots, illustrations, banners. At this setting you reliably get a smaller file than the source PNG while keeping fine detail intact.

Transparency is fully preserved. WebP has a built-in alpha channel, so a transparent PNG converts to a transparent WebP — no flattening, no white backgrounds. This is the most important practical difference between WebP and JPG: WebP is a real PNG replacement, not just a JPG one.

How to use this tool

  1. Drop your .png file onto the drop zone above.
  2. The image is decoded into a canvas and re-encoded as WebP via your browser's WebP encoder.
  3. Click Download. The widget reports the new file size and the percentage saved versus the source PNG.

Files never leave your device. The Canvas API runs locally; open DevTools and watch the Network tab to verify.

Should you serve only WebP, or include a PNG fallback?

In 2026, every browser that matters supports WebP — Chrome, Edge, Firefox, Safari 14+ (released 2020), Opera, Samsung Internet, and all derived browsers. For mainstream consumer audiences, serving WebP only is safe.

If you serve an audience on locked-down corporate IE11 — or an embedded device, kiosk, or legacy CMS preview pane — the HTML <picture> element gives you painless fallback:

<picture>
  <source srcset="hero.webp" type="image/webp" />
  <img src="hero.jpg" alt="…" />
</picture>

Modern browsers pick the WebP; everything else falls back to the JPG. Zero JavaScript, no UA sniffing.

Frequently asked questions

WebP typically produces files 25–35% smaller than PNG at visually identical quality, and supports transparency, so it's a near-drop-in replacement for the modern web. Faster page loads, lower hosting bandwidth, better Core Web Vitals — all without sacrificing alpha channel support.

Working in After Effects?

Building motion graphics in After Effects? Subflow generates frame-accurate captions inside AE — three styles, broadcast positioning. Try it at subflow.cc.

See Subflow