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JPEG File Format (.jpeg)

.jpeg and .jpg are the same JPEG-compressed image format under two different extension spellings, a split that dates to the three-character extension limit of MS-DOS and early Windows.

.jpegImage Files

JPEG at a glance#

Full nameJoint Photographic Experts Group JFIF format
File extension.jpeg
CategoryImage Files
DeveloperJoint Photographic Experts Group
First released1992
MIME typesimage/jpeg
Other extensions.jpe.jfif.jif
CompressionLossy
SpecificationISO/IEC 10918-1 / ITU-T T.81
FileFlip supportFileFlip reads and writes this format

What a .jpeg file can hold#

These are the things a JPEG file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.

Transparency (alpha channel)No
AnimationNo
Lossless compressionNo
Embedded metadataYes
Colour profilesYes
High dynamic rangeNo
Multiple images or pagesNo

Strengths and limitations of JPEG#

What JPEG does well

  • Identical image quality and compression to a .jpg file, since it's the same format
  • The full four-letter spelling matches the standard's own name, so it reads unambiguously on Unix and macOS systems that never had an extension-length limit
  • Opens in the same software as .jpg with no conversion needed
  • Recognized by every current browser and operating system regardless of which spelling is used

Where JPEG falls short

  • Some older Windows software and web forms still only whitelist the three-letter .jpg spelling
  • Having two accepted extensions for one format occasionally confuses batch scripts or upload filters that check the extension literally
  • Inherits every JPEG limitation: no transparency, no animation, and lossy recompression on every re-save

Save an image as .jpeg over .jpg when a system, script, or personal convention specifically expects the full four-letter extension; the image data itself doesn't care which one is used.

Rename or export as .jpg instead of .jpeg when a target system, upload form, or older piece of software only recognizes the three-letter extension, which is the more common expectation today.

How to open a .jpeg file#

A .jpeg file opens in the programs below, grouped by the platform you are on. If you would rather not install anything, FileFlip converts JPEG into a format your machine already opens, and it does it in the browser tab rather than on a server.

PlatformPrograms that open it
WindowsPhotos, Paint, IrfanView, Adobe Photoshop
macOSPreview, Photos, Adobe Photoshop, Affinity Photo
LinuxGIMP, eog (Image Viewer), gThumb, ImageMagick
iOSPhotos, Files
AndroidGoogle Photos, Gallery
WebFileFlip

JPEG questions people ask#

What's the difference between .jpeg and .jpg?

There is no difference in the image data. Both extensions point to the same JPEG-compressed file format; the file's pixels, compression, and quality are identical either way, only the name on the extension changes.

Why does JPEG have two spellings of its extension?

MS-DOS and early Windows used the FAT filesystem's 8.3 naming rule, which limited every file extension to three characters, so the four-letter '.jpeg' wouldn't fit. Software on those systems saved files as '.jpg' instead, while Unix and early Macintosh systems, which had no such limit, kept the full '.jpeg' spelling the JPEG committee had used in its own 1992 documentation.

Why do people still use .jpg if the 8.3 limit is gone?

Windows removed the three-character extension limit in 1995 with long filename support in Windows 95, but by then .jpg was already the default on the world's most common desktop operating system. Habit, existing software defaults, and camera firmware kept it the more common spelling even after the technical reason for it disappeared.

Does renaming a .jpeg file to .jpg change anything?

No. Renaming the extension only changes the filename, not the bytes inside the file, so a .jpeg renamed to .jpg opens and displays exactly the same image. Any image viewer or editor that reads one extension reads the other.

Which extension should I use, .jpg or .jpeg?

.jpg is the safer default because a few older tools and upload forms still only recognize three-letter extensions, but .jpeg works everywhere modern. Pick whichever a target platform expects, or default to .jpg since it's the more widely assumed spelling.

Converting JPEG files#

Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.