Why a picture ended in .jfif, and what to do with it
A picture saved from a website sometimes lands on your computer ending in .jfif rather than .jpg, and then an upload form, an editor or a print kiosk will not take it. Nothing is wrong with the picture. JFIF is the name of the layout nearly every JPEG has always used inside, and the ending is a quirk of how the file was saved, not a different kind of image.
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Which tool you need
A .jfif picture that has to go somewhere as a PDF
JFIF to PDF. The picture is recognized by what is inside it, so the ending makes no difference, and its data goes into the PDF untouched.
The form asks for a JPG, not a PDF
You may not need a converter at all. Renaming the file so it ends in .jpg satisfies most forms, because the picture inside already is one.
A saved picture that is really a WebP or a PNG
Image to PDF. This page takes JPEG pictures only, and a file saved from the web is sometimes another format whatever its name says.
The PDF has to come in under a size a form sets
Resize PDF on the result, which aims for the size the form names, such as 200 KB or 1 MB.
Where the .jfif ending comes from
JPEG is the compression; JFIF is the small header that wraps it so programs agree on how to read it. Most software has always named such files .jpg, but some browsers on Windows save web pictures as .jfif, because of how the system was set to name JPEG pictures rather than anything about the picture itself.
That is why the same picture can be a .jpg on one computer and a .jfif on another. An app that checks only the ending sees a format missing from its list, and turns away a file it could have read perfectly well.
What happens to the picture's data
A PDF can hold JPEG data directly, so the picture is copied into the file still compressed rather than decoded and saved again, which is the step that costs a little quality each time it happens. The PDF ends up roughly as large as the pictures put together.
What is not copied is the record around the picture: the camera model, the date and any location a phone stored there stay behind. A picture marked as mirrored is the only one redrawn, so that it reads the right way round in the PDF.
What to know before you start
- JPEG pictures only, whichever of .jfif, .jpg or .jpeg they end in.
- A file named .jfif that holds some other format is turned away; Image to PDF reads most of those.
- The words in a picture of a document cannot be searched in the PDF.
- Camera and location records inside the picture are not carried over.