Convert JFIF to PNG
A lossless PNG copy of every .jfif picture, made on your device.
- Nothing is uploaded
- Works offline after first visit
- Open source
- No watermark · limit is your device’s memory; phones hold less
Convert .jfif images to lossless PNG in your browser. It is free, needs no account and adds no watermark, and your files are not uploaded: everything runs in your browser on your device. The size limit is your device’s memory, and phones hold less; give the page a short while after one visit to save itself for offline use, and then it works offline.
Done
Free, no ads. Support StayPut
Open the network tab. Your files never appear in it.
Add files and run the tool to see every request this tab makes.
Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.
A .jfif file is an ordinary JPEG with an unusual extension, typically a picture saved from the web on Windows. PNG is the right destination when the image is going into a design tool, a slide deck or an edit you will save several times: PNG is lossless, so every later save keeps exactly the pixels you have now instead of adding another round of JPEG artefacts.
Your browser decodes each .jfif file inside this tab and writes a PNG. Expect the PNG to be several times larger than the JFIF, because PNG stores every pixel without loss. A PNG made from a JPEG has no transparency to begin with; converting does not add any.
Have another type of picture? Convert any image to PNG takes PNG, WebP, HEIC, GIF, BMP, AVIF and more.
How it works
- Drop your JFIF files onto the page, or tap to pick them. Batches are fine.
- There are no quality settings: PNG is lossless, so the output matches the decoded image exactly.
- Download each PNG, or all of them as one zip.
In your browser, not on a server
Stayput first reads the opening bytes of each file, where every image format writes its signature, so it knows what the file really is whatever it is called. Your browser decodes JPG, PNG, WebP, GIF, BMP, AVIF and SVG itself; TIFF goes through UTIF.js, HEIC through the libheif WebAssembly decoder, and JPEG XL (or AVIF, in a browser without native support) through the Squoosh decoders, all served from this site and cached. The browser re-encodes JPG, PNG and WebP; PDF, ICO, GIF, BMP and TIFF files are written by small encoders in the page. Nothing here needs a server.
Compared with upload-based tools: Online converters upload your image, convert it on their machine, keep it for hours and cap you at a few files a day. This does the same conversion on your device, for as many files as your device’s memory can hold, with no upload to wait for.
Verify it yourself. Give the page a short while after one visit to save itself for offline use, then turn off Wi-Fi or switch to airplane mode and run the tool again. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.
Questions
Will the PNG look better than the JFIF?
No. Converting cannot bring back detail the JPEG compression already removed. What PNG gives you is a copy that loses nothing more when you edit and save it again.
Why is the PNG so much bigger?
JPEG, and so JFIF, discards detail to stay small. PNG keeps every pixel. A 300 KB photo commonly becomes a 2 to 4 MB PNG. If size matters, convert to JPG instead.
Can I convert many at once?
Yes. Drop as many files as you like; download them one by one or as a single zip.
Are the images uploaded?
No. Decoding and encoding happen in your browser tab and the files never leave your device.
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Other conversions
- JXL to PNG
- JFIF to JPG
- GIF to PNG
- BMP to PNG
- TIFF to PNG
- PSD to PNG
- ICO to PNG
- Any image to PNG
- HEIC to PNG
- HEIF to PNG
- PNG to Word
- PNG to Base64
- PNG to text
- Video to PNG
- PNG to SVG
- PNG to PDF
- PDF to PNG
- Compress image to 2 MB
- Resize image to 3000×3000
- Resize image to 1920×1080
- Resize image to 1024×1024
- Resize image to 512×512
Guides
- A free Zamzar alternative with no daily limitZamzar's free service limits how many files you can convert and how big each can be. Here is an alternative with no such cap.
- A free FreeConvert alternative with no processing time capFreeConvert's free plan limits the processing time for each file and for the day. Here is an alternative with nothing to time out.
- JPG, PNG, WebP or HEIC: which image format to useA practical rule for each job, and the conversion to get there.
- Is CloudConvert safe?For most files, yes: it is an established, certified service. The real question is whether a given file should leave your computer at all.
- Is FreeConvert safe?Yes: FreeConvert.com is a legitimate converter with a clear deletion policy, and fine for everyday files. Whether it is safe for a particular file depends on whether that file should be uploaded anywhere.