image tool
JPG to PNG
Write a PNG from a JPEG without leaving the page. The output is a real PNG file with a real signature, and the dimensions are read back from the encoded result.
Add files
Drop JPEG images here, or choose files. Everything stays on this device.
Waiting for files
Accepted input
- JPEG images, up to 10 at a time
Limits
- Up to 20 MB per image and 10 images per batch.
- Up to 40 megapixels per image, checked before the pixels are allocated.
- JPEG has no transparency, so the PNG cannot gain an alpha channel from this conversion.
Local processing
- Files are read in your browser and are never uploaded to a server.
- Nothing is stored after you close or reload the page.
How to use JPG to PNG
- Add one or more JPEG images.
- Press Convert to PNG.
- Download the PNG files; each result states its dimensions.
What it does
- Produces a genuine PNG stream, not a JPEG with a new extension.
- Handles several files at once and keeps every result separate.
- Reports the encoded dimensions instead of repeating the values you typed.
Limits and things to know
- A lossy JPEG cannot be restored: the artefacts already in the source stay in the PNG.
- PNG files are usually larger than the JPEG they came from because the conversion keeps every pixel detail.
- EXIF, GPS and camera metadata are dropped when the image is re-encoded.
Example
Getting a screenshot out of a photo format
A screenshot saved as .jpg has jagged text because JPEG blocks the edges. Converting it to PNG fixes nothing by itself, but it gives you a lossless format to edit and re-save before you archive it.
Frequently asked questions
Why is my PNG bigger than the JPG?
Because JPEG throws away detail to save space. PNG stores what it is given, so the same pixels usually need more bytes.
Does this add transparency?
No. JPEG cannot hold transparency, so there is no alpha channel to bring across.
Is the file a real PNG?
Yes. The encoder writes the PNG signature and chunk structure, and the tool re-reads the header of the result to confirm the format and size.
Runs entirely in your browser on ap98.com. Files are never uploaded.