MundoKit

WebP to JPG / PNG Converter

Choose WebP files and export JPG or PNG locally. Set a background or preserve transparency in PNG.

Use this local tool with JavaScript enabled. Your inputs stay in your browser.

How it works

The browser decodes each file, draws it onto an sRGB canvas at its decoded dimensions, and encodes a new image. JPG always flattens transparency onto your chosen background. PNG can preserve alpha or flatten it. JPG quality is the entered percentage divided by 100; it is an encoder hint, not a promised file size. PNG ignores quality. No resizing or size rounding is applied.

Local safeguards allow up to 20 files, 30 MB (30,000,000 bytes) each, 16 million decoded pixels and 16,384 pixels per side. Container dimensions are validated before native decoding, and decoded dimensions are checked again. Unsupported dimension layouts are rejected. Processing is sequential. Download each successful result from its link; no ZIP library is used. Changing inputs clears old outputs. A failed file does not stop the rest of the batch.

Worked examples

Dimensions stay the same

A 1,200 × 800 image has 960,000 pixels and exports at 1,200 × 800. Selecting JPG quality 90 passes 0.9 to the browser encoder; output byte size depends on the image.

Transparent PNG or solid JPG

With transparency enabled, PNG keeps alpha. Choosing JPG with background #ffffff always flattens it to white, even if the transparency checkbox was previously selected.

Frequently asked questions

Are my files uploaded?
No. Files are decoded and encoded in your browser. Download links point to local Blob URLs.
Why can conversion fail?
Your browser may not decode this image variant, the file may be damaged, or local size safeguards may reject it. There is no server or external decoder fallback.
Does PNG restore lost quality?
No. PNG preserves the decoded pixels without JPG-style lossy encoding; it cannot recover details already lost in the source.
Can this convert animations?
No. WebP animation chunks or the animation flag cause rejection. This tool does not extract frames.
Will colors and metadata be preserved?
Original metadata is not copied. Inspect the output before replacing the original.

Sources

Last reviewed 2026-11-14. The method is written out above so you can check our math.