Image Converter re-encodes images entirely inside your browser using the Canvas API's native decode/encode support — no file is ever sent anywhere to be processed. Each image is decoded into an in-memory bitmap, drawn onto an off-screen canvas, and re-encoded to your chosen output format, all inside a background worker so the rest of the page stays responsive even on a large batch.

PNG is best for graphics, logos, and anything needing transparency, since it's lossless. JPG suits photographs well, trading a small amount of quality for a much smaller file. WebP typically produces the smallest files of the three at a comparable visual quality, and is supported by every modern browser — a good default when file size matters most.

Converting a batch of files processes them one at a time inside a single worker rather than all at once, keeping memory use predictable regardless of how many images you drop in. Once every file is converted, you can download them individually or as one zip archive.

The PNG-to-JPG transparency behavior is worth understanding before you hit convert on a logo or icon: JPG has no concept of a transparent pixel at all, so any transparent area in a source PNG gets filled with solid white during conversion rather than silently dropped or left broken. If the image is destined for a page with a non-white background, that filled area will show as a visible white box — WebP, which does support transparency, is the better target format in that case. This is exactly the kind of format-specific gotcha this tool tries to surface up front (in the FAQ below and the quality-preview step) rather than letting you discover it after the fact.

Choosing between the three output formats mostly comes down to what the image actually is: PNG for anything that needs pixel-perfect reproduction or transparency (logos, screenshots, icons), JPG for photographs where a small, generally imperceptible quality trade-off buys a much smaller file, and WebP when you want the smallest possible file and don't need universal support in older software. See the lossless vs. lossy compression guide for the full reasoning behind that trade-off.