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PNG to WebP Converter

Convert PNG to WebP with transparency preserved — runs locally in your browser.

Written by Golam Rabbani, Founder & Lead Engineer

Local conversion only; nothing is uploaded.

How to use this png to webp converter

  1. Choose a PNG file from your device.
  2. Move the quality slider — 85 is a strong default that balances size and clarity.
  3. Press "Convert to WebP" to re-encode the image with the browser's native WebP encoder.
  4. Preview the result and confirm the file size shrank as expected.
  5. Click "Download WebP" to save the converted file locally.

About this png to webp converter

A PNG-to-WebP converter re-encodes a lossless PNG into Google's modern WebP format, giving you a file that is dramatically smaller while retaining the same on-screen appearance. WebP supports both lossless and lossy compression modes as well as a full 8-bit alpha channel, so it handles transparent graphics and photographic content alike — something neither JPEG nor plain PNG can do in a single format. For modern websites, WebP is almost always the right output choice for reducing page weight without sacrificing visual quality.

The conversion pipeline is entirely browser-side. After you choose a file, the tool decodes the PNG using the browser's native createImageBitmap API and draws it onto an off-screen HTML canvas at the original pixel dimensions. The canvas.toBlob method then re-encodes that pixel data as WebP at the quality level you set with the slider (1–100, mapped to the underlying 0–1 range the encoder expects). Transparency is preserved end-to-end because WebP carries a full alpha channel. Your image is never uploaded, never logged, and never leaves your browser tab.

As a concrete example: a 3.1 MB PNG screenshot converted at quality 85 typically produces a WebP around 220 KB — roughly a 14× reduction — with crisp text and sharp edges intact. Pushing quality to 95 lands around 400 KB and is visually indistinguishable from the original on even high-DPI displays.

WebP is supported by Chrome, Firefox, Edge, and Safari 14+, covering well over 95% of global traffic. For legacy email clients or print pipelines that may not recognise WebP, fall back to PNG or JPEG.

FAQ

Are my images uploaded anywhere during conversion?
No, conversion runs entirely in your browser using the canvas API. The PNG is decoded and re-encoded locally with no network traffic.
Is transparency preserved in the WebP output?
Yes. WebP supports an 8-bit alpha channel, so transparent and semi-transparent pixels in your PNG are preserved bit-perfect in the output.
How much smaller will the WebP be compared to the PNG?
For graphics and screenshots the WebP is typically 5-15x smaller at quality 85; for photographs the ratio can hit 20x or more. Savings depend on how much fine detail the image contains.
What quality should I choose?
85 is a good default for general use. Drop to 75 for very aggressive size savings on photographs, or push to 95 for archival-grade output that is hard to distinguish from the source.
Which browsers can display WebP?
Chrome, Firefox, Edge, and Safari 14+. That is over 95% of global traffic in 2026. For older browsers or non-web destinations, fall back to PNG or JPEG.