JPEG and JPG are exactly the same image formats. There is no difference between a .jpg image and a .jpeg image — they both use exactly the same JPEG compression algorithm and store image data in the same way.
The difference is purely in the suffix, as it is a legacy issue from the early days of computing. JPEG was created in 1992 by the Joint Photographic Experts Group. When Microsoft introduced early versions of Windows, the system imposed a limitation: extensions had to be 3 characters.
This forced the 4-character .jpeg suffix to be abbreviated to .jpg for Windows users. Non-Windows systems, not having this three-character restriction, continued using the complete .jpeg extension from the outset.
Although both file types function the same in virtually all today's programs, some situations when a system requires the .jpeg file type. In these cases, converting from .jpg to .jpeg is all that is needed.
No image data conversion is necessary — read more just renaming the file extension resolves the problem almost always.
Try alljpgconverters.com offering a totally free online JPG to JPEG solution with no download required.