J2K File

What are J2K files and how to open them

Are you having problems opening a J2K file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your J2K files.

What is a J2K file?

J2K files have multiple uses, and JPEG 2000 Image is one of them. Read more about the other uses further down the page.

JPEG 2000 Image File

The .j2k file extension is a raster bitmap image file type that is used by Joint Photographic Experts Group (JPEG) 2000 files. The JPEG 2000 format uses wavelet-based image compression instead of the DCT (Discrete- Cosine- Transform) compression and stores metadata.

The metadata or the description information of the .j2k file is coded in XML as compared to the standard .jpeg or .jpg format that is basically formatted with EXIF data.

JPEG 2000 files are saved with a .j2k extension but typically, they can also use either a JP2 or JPX extension. For Windows, JPEG 2000 files can be open using the most popular image viewers and editors like the ones pioneered by Adobe and Corel. Though they are still not as common as standard JPG files, J2K files can support 16-bit color, alpha transparency, and lossless compression.

How to open J2K files

We have identified five J2K openers that are compatible with this specific type of J2K file.

Programs that open JPEG 2000 Image files

Last updated: January 22, 2025

All known file formats using extension .J2K

While JPEG 2000 Image File is a popular type of J2K-file, we know of 2 different uses of the .J2K file extension. Different software may use files with the same extension for different types of data.

Joy2Key Settings

We know that one J2K format is Joy2Key Settings. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

While we have not verified the apps ourselves yet, our users have suggested ten different J2K openers which you will find listed below.

Various apps that use files with this extension

These apps are known to open certain types of J2K files. Remember, different programs may use J2K files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about J2K file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.