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Difference Between JPG and JPEG

Updated on August 5, 2022
Difference Between JPG and JPEG

If you work with images and photographs online, you've probably seen both JPG and JPEG extensions floating around. This can sometimes be confusing when choosing the suitable image file format because you don't know which file format to use.

Using the right image file format for your images can save valuable space on your hard drive or provide faster loading times on your website.

This article will show you if and how JPG and JPEG differ and which file type is better for your project.

Difference between JPG and JPEG


JPEG is a file extension that stands for Joint Photographic Experts Group. The ISO standard was initially released back in 1992. It is a bitmap compression format, most commonly used for lossy compression, with compression ratios ranging from 10:1 to 20:1. The compression ratio can be adjusted, which means you can determine your balance between storage size and quality. The JPEG extension is most commonly used by digital cameras and photo sharing devices.

While the JPEG format is excellent for color and photographs, it is also important to note that there is a slight loss of quality due to compression. And editing and re-saving only degrade the quality, even though it might be negligible. One way to minimize this is to work with the RAW JPEGs, determine your edits, and then save the final version without re-saving it multiple times.

The MIME media type for JPEG is image/jpeg (defined in RFC 1341), except in older Internet Explorer versions, which provide a MIME type of image/pjpeg when uploading JPEG images. JPEG is also defined with the additional extensions, .jpe, .jif, .jfif, and .jfi.


Then we have the JPG format. There are actually no differences between the JPG and JPEG formats. The only difference is the number of characters used. JPG only exists because they required a three-letter extension for the file names in earlier versions of Windows (MS-DOS 8.3 and FAT-16 file systems). So .jpeg was shortened to .jpg. While Windows and/or DOS had this limitation, UNIX did not, so UNIX and MAC users continued using the .jpeg extension. Newer versions of Windows, of course, now accept more characters in their file extension. However, .jpg was already being used by most people (and programs needed to work with MS-DOS 8.3), so it is still the most common extension.

Photo editing programs like Adobe Photoshop and Gimp all save JPEGs by default to the .jpg extension on both Windows and MACs. And if you were wondering, you can change the extension both ways, and the file will continue to work.


As you can see, there is no difference between JPG and JPEG. JPG simply arose from a three-letter file extension limitation with earlier versions of Windows or DOS. You can convert your photos to both JPG and JPEG to take advantage of the small file size and vibrant colors since they are the same type.

So choosing whether to go with JPG or JPEG isn't as difficult as you thought, is it?

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