JFIF Viewer

Open a .jfif file in your browser and read what is actually inside it: real pixel dimensions, byte size, and whether the header is JFIF, Exif or a plain JPEG. Nothing is uploaded and nothing is installed.

Drop a file to view it

Read locally by your own browser. Never transmitted.

What the inspector reports

  • Header type. Read from the first bytes of the file rather than the extension: FF D8 FF E0 with JFIF\0 at offset 6 means a JFIF container; FF D8 FF E1 with Exif\0\0 means an Exif file from a camera or phone.
  • True dimensions. Decoded pixel width and height, which is often not what a file manager reports for a mislabelled file.
  • Exact byte size and the megapixel count.
  • Whether the extension matches the content. A .jfif file that actually starts 89 50 4E 47 is a PNG in disguise — a common cause of "this file won't open anywhere".

For the meaning of each header field, see the JFIF format reference.

Why an in-browser viewer is the safer way to open an unknown file

If somebody sends you a .jfif you were not expecting, uploading it to an online viewer means handing an unknown file to a third party and getting back a page you have to trust. Rendering it locally in a sandboxed browser tab avoids both problems: the file goes nowhere, and browser image decoders are among the most heavily fuzzed and patched code in existence.