JPG to PNG

How do I convert JPG to PNG?

1. Drop one or more JPG files onto the drop zone, or click to browse.
2. Check the file list; there are no settings to adjust because PNG output is lossless.
3. Click Convert to PNG.
4. Download the PNG, or Download all as ZIP when converting several files.

Converting JPG to PNG does not recover any detail the JPEG compression already threw away, so it is worth being clear about when it helps. The main reasons are that a tool or website insists on PNG, that you plan to edit the image several times and do not want each save to add more JPEG artefacts, or that you want to add transparency in an editor afterwards. PNG is also the right container if you are about to paste the image into a document or slide where the software will otherwise recompress it.

The tool decodes the JPEG with createImageBitmap in a Web Worker, draws it to an OffscreenCanvas and encodes the canvas as PNG. Every pixel from the decoded JPEG is stored exactly, which is why there is no quality slider. The trade-off is size: a 500 KB photo JPG typically becomes a 1.5 to 2.5 MB PNG, and images with lots of fine texture can grow more. That is normal and not a fault; PNG's deflate compression is simply not designed for photographic noise.

The output is a 24 bit RGB PNG with no alpha channel, because a JPG has no transparency to preserve. Open it in an image editor to add one. Colour is converted to standard sRGB and any EXIF or ICC profile data in the JPEG is not copied across, so a photo taken in a wide gamut profile may look marginally different in colour-managed software. If you need to keep metadata, take a copy of the original before converting.

If your goal is a smaller file rather than a lossless one, this is the wrong direction; try Compress JPG or JPG to WebP. If you want a PNG that is also smaller in pixels, Resize Image can output PNG at a new size in one step. And if you later need to go back, PNG to JPG re-encodes with a quality setting and a background colour.

Everything runs on your device. The JPG is decoded and re-encoded in browser memory, and the PNG is offered as a download without touching a server. There is no size limit and no limit on files per batch.

How it works: this tool uses your browser's Canvas and WebCodecs APIs, plus libheif for HEIC. No server is involved, so Kilnfile never sees your file. Last reviewed 20 September 2026.

Frequently asked questions