JPG to PNG Converter - Convert JPG to PNG Online Free
Convert JPG and JPEG files to lossless PNG directly in your browser. Batch conversion, no quality slider, no uploads.
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Supports JPG
What JPG to PNG Conversion Does
This tool decodes your JPG onto an in-browser canvas and re-encodes the resulting pixels as a PNG using the browser's own encoder. Nothing is uploaded — the whole decode-and-re-encode cycle runs on your device. The two formats differ in ways that explain almost everything you'll notice about the result. JPG is a lossy format with no alpha channel: the encoder throws away visual detail to shrink the file, and it stores no transparency information at all. PNG is lossless and does support alpha: every pixel handed to the encoder comes back out exactly as it went in, and file size depends purely on how compressible the image content is. That difference is why converted files are usually larger, often several times larger for photographs. A photo is full of fine noise and gradients that PNG's lossless compression cannot discard, while JPG was free to smooth them away. Flat graphics, screenshots, logos, and line art compress far better and sometimes come out close to the original size. It's worth being clear about what the conversion does not do. It does not restore detail the JPG encoder already discarded — that data is gone from the file, and re-encoding it losslessly just preserves the damage more faithfully. It does not create a transparent background, because a JPG has no transparency to carry over; every pixel arrives fully opaque. What you get is an exact, lossless copy of the image as it exists right now, one that stops accumulating compression artifacts from this point forward.
Why You'd Convert JPG to PNG
The reason is almost always either a destination that demands PNG, or an editing workflow that shouldn't keep re-compressing.
How to Convert JPG to PNG
There are no encoder settings to weigh here — PNG is lossless, so the only decision is which files to convert.
Add one JPG or JPEG, or drop in a whole folder — every file runs through the same pass
Apply the conversion; there's no quality slider, since PNG encoding has nothing to trade away
Check the preview and the new file size — expect photos to grow, flat graphics much less so
Download the PNG, or grab the whole batch as a single ZIP archive
Frequently Asked Questions
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