How to Change Between JPG and JPEG File Extensions

JPG and JPEG are two names for the same file format. The three-letter .jpg extension became common because older versions of Windows limited extensions to three characters, while .jpeg is the full name. Both contain identical image data, so converting a JPG to JPEG, or a JPEG to JPG, is usually just a matter of renaming the file. No re-encoding is needed, and the picture does not change.

Before you start

Changing the extension happens locally in your file manager. You do not need a converter app or an online service, and nothing has to leave your device. If you still choose a web-based converter, check its own statements on how uploaded files are stored and deleted before sending personal photos, and treat those statements as something to verify rather than a guarantee.

• Make sure file name extensions are visible, otherwise you may create a double name such as photo.jpg.jpeg.
• Confirm the file really is a JPEG. A picture saved as HEIC, PNG or WebP will not become a JPEG just because you change its extension.
• Keep a copy of the original if the file matters, especially before renaming many files at once.

Step-by-step instructions

Windows

• 1. Open File Explorer and turn on file name extensions. In Windows 11 this is under View, then Show, then File name extensions. In Windows 10 it is a checkbox on the View tab.
• 2. Right-click the image and choose Rename, or select it and press F2.
• 3. Replace .jpg with .jpeg, or .jpeg with .jpg, and press Enter.
• 4. Windows warns that changing an extension might make the file unusable. For a genuine JPEG, confirm with Yes; the file will open normally.

macOS

• 1. In Finder, open Settings (Preferences on older versions), go to Advanced and enable Show all filename extensions.
• 2. Select the file, press Return, and edit the extension.
• 3. When Finder asks whether to keep the old extension or use the new one, choose the new one.
• 4. To change several files, select them, right-click, choose Rename, and use the Replace Text option to swap .jpg for .jpeg or the reverse.

Renaming versus exporting

Some people open the image in an editor and save it again with the other extension. That works, but it re-applies lossy compression, which can slightly reduce quality each time and may strip metadata. Renaming is the better choice when the only goal is to switch between .jpg and .jpeg. Use an editor or photo format converter only when you need an actual format change, such as turning a PNG or HEIC file into a JPEG.

Check the output

• Open the renamed file in your usual image viewer; it should display exactly as before.
• Compare file size and pixel dimensions in the file properties or Get Info window. After a plain rename both stay the same, and the aspect ratio is unchanged.
• Look at the file type shown by the system. It should still report a JPEG image.
• If you exported instead of renaming, expect the file size to differ, and check the image at full size for compression artifacts.

Keep in mind that JPEG has no support for transparency. If you converted from a format with transparent areas, such as PNG, those areas will be filled with a solid color in the resulting JPEG.

Common problems and next steps

A website or app rejects the file. Some upload forms accept only one of the two spellings. Rename the file to the extension the form lists; because the data is identical, this is a valid fix.

The file now has two extensions. If you renamed while extensions were hidden, the result may be something like image.jpg.jpeg. Turn extensions on as described above and remove the extra part.

The file will not open after renaming. It was probably not a JPEG to begin with. Change the extension back, then open the image in an editor or converter and export it as JPEG to perform a real conversion.

Other variants. You may also see .jpe or .jfif. These normally hold the same kind of JPEG data and can often be renamed to .jpg in the same way, but verify the file opens correctly afterwards.