Convert Images to Any Format

What conversion does and does not cost you

Converting to a lossless format — PNG, or WebP in lossless mode — preserves your pixels exactly. Converting to a lossy format (JPG, lossy WebP, AVIF) discards data permanently, in exchange for a much smaller file.

The case worth avoiding is converting between two lossy formats. A JPG turned into a lossy WebP has been through two rounds of quantisation, and the second round treats the first round's artefacts as real detail worth preserving. Always convert from the highest-quality copy you have, not from a file that has already been compressed.

Which target format to pick

The answer depends almost entirely on where the file is going:

• For your own website: WebP. Typically 25–35% smaller than JPG at the same visual quality, supported by every current browser.
• For sending to someone else: JPG. It is the most compatible image format in existence and never gets rejected.
• For anything with a transparent background: PNG as a master, lossy WebP for the web. JPG cannot store transparency at all.
• For screenshots and images containing text: PNG or lossless WebP — sharp edges are the worst case for lossy compression.
• For large hero images where bandwidth matters: AVIF, which compresses hardest but encodes slowly.

The transparency trap

Converting a transparent PNG to JPG is the most common conversion mistake, because JPEG has no alpha channel and no way to represent one. The transparency has to be resolved against something, and the software picks — usually white, sometimes black.

Nothing is broken and nothing can be recovered afterwards; the alpha channel was discarded at export. If your cut-out came back with a white background, this is why. Re-export from the original as PNG or WebP.

Why this runs on your device

Conversion happens in your browser using the same canvas and codec support the browser already ships for displaying images. Nothing is uploaded, which means no file size ceiling imposed by a server, no queue, and no per-image cost — so batch conversion is just a matter of waiting.

It also means the tool works on files you would not want to hand to a service: scanned documents, identity paperwork, medical images, unreleased work.