JPG and JPEG are identical file formats with different names
There is no conversion needed. JPG and JPEG are the same image format — the only difference is the file extension. JPG is the three-letter abbreviation; JPEG is the four-letter spelling of Joint Photographic Experts Group, the standard that created it. Your operating system and image software treat them identically. A file named photo.jpg and one named photo.jpeg contain the exact same image data and will open in the same programs.
If you need to change a filename from .jpg to .jpeg (or vice versa), you rename the file. If you have a JPG file and want to save it as JPEG, you simply change the extension in the filename. No image quality is lost, no conversion happens, and no special software is required.
Key Takeaways
- JPG and JPEG are the same format with different filename extensions — renaming one to the other does not change the image itself.
- On Windows, right-click the file, select Rename, and change the extension from .jpg to .jpeg or vice versa.
- On Mac, select the file, press Return to edit the name, change the extension, and confirm the change.
- Some older software or specific systems may expect one extension over the other, but modern programs open both without any difference.
How to rename a JPG file to JPEG on Windows
Right-click the JPG file on your computer. A menu will appear with several options. Select Rename from the list. The filename will become editable — the text will highlight or show a cursor.
Find the file extension at the end of the name. It will read something like photo.jpg. Change jpg to jpeg so it reads photo.jpeg. Press Enter on your keyboard. Windows will ask you to confirm the extension change. Click Yes. The file is now renamed and will open exactly as it did before.
If you do not see the file extension, you may have hidden extensions turned on. Open File Explorer, click the View tab at the top, and check the box next to File name extensions. The extensions will now be visible for all files.
How to rename a JPG file to JPEG on Mac
Click once on the JPG file to select it. Press the Return key on your keyboard. The filename will become editable with a text cursor. The extension may be highlighted separately or included in the editable text depending on your macOS version.
Change jpg to jpeg at the end of the filename. Press Return again. macOS will ask whether you want to use the new extension. Click Use .jpeg to confirm. The file is now renamed and behaves identically to before.
When you might need to use one extension over the other
Most modern software, websites, and devices accept both .jpg and .jpeg without any problem. However, some older programs or specific systems may expect one extension rather than the other. For example, an older photo editing program might only recognize .jpg files in its file browser, or a specialized medical imaging system might require .jpeg specifically.
If you are uploading a file to a website and it rejects your .jpg file, try renaming it to .jpeg and uploading again. The reverse is also true — if a .jpeg file is rejected, try .jpg. This solves the problem in most cases where an extension mismatch is the issue.
Batch renaming multiple files at once
If you have many JPG files to rename to JPEG, renaming them one at a time is slow. Windows includes a built-in batch rename tool. Select all the files you want to rename by clicking the first one, holding Shift, and clicking the last one. Right-click and select Rename. Type a new name — Windows will rename all selected files with that name followed by a number in parentheses, like photo (1).jpeg, photo (2).jpeg, and so on.
On Mac, select all the files, right-click, and choose Rename [number] items. A dialog box will appear with options to find and replace text in the filenames. Type jpg in the Find field and jpeg in the Replace field, then click Rename. All selected files will be renamed at once.
What actually happens when you change the extension
Changing the extension from .jpg to .jpeg does not recompress the image, alter the colors, or change the file size. The image data inside the file remains exactly the same. You are only changing the label that tells your operating system which program should open it by default.
This is different from converting between formats like JPG to PNG or JPG to WebP, which would require actual image processing software and would change the file itself. Renaming .jpg to .jpeg is purely a filename change with no processing involved.
Frequently Asked Questions
Will changing jpg to jpeg affect my image quality?
No. The image data does not change when you rename the file. The quality remains identical because you are only changing the filename extension, not processing the image itself. The file size also stays the same.
Can I change jpeg back to jpg?
Yes, the process is identical in reverse. Right-click the file, select Rename, change .jpeg to .jpg, and press Enter. Confirm the extension change. The file will work exactly as before.
Why do both extensions exist if they are the same?
Windows originally limited filenames to three-letter extensions, so JPG was used. JPEG is the full, official name of the format. When Windows later allowed longer extensions, JPEG became common, but JPG remained in use. Both are correct and interchangeable.
What if my file won't rename?
The file may be open in another program. Close any photo viewer, editor, or browser window that has the image open, then try renaming again. If it still will not rename, the file may be read-only — right-click it, select Properties (Windows) or Get Info (Mac), and uncheck the read-only box.
Do I need special software to change jpg to jpeg?
No. Renaming is a basic file operation built into Windows and Mac. You do not need to download or install anything. Simply right-click the file and rename it using your operating system's built-in tools.