What Is a DNG File?
A file with the DNG file extension is most likely an Adobe Digital Negative Raw Image file. The format is a response to the lack of an open standard for digital camera raw formats. Other raw files can be converted to DNG so that a wider variety of software can use them. The DNG file structure provides not only a way of storing an image but also the means for preserving additional information about the photo, such as metadata and color profiles.
Other Uses of the DNG File Extension
Some DNG files are Virtual Dongle Image files. They are digital copies of physical dongles that some software might require to activate the program. A physical dongle acts as a key that holds software license information, so a virtual dongle is used for the same purpose, but with dongle emulators.
How to Open a DNG File
DNG files can be opened with several image viewers, including the built-in Photos app in Windows and macOS, Photopea, Able RAWer, and Canvas X. While not free, Photoshop and Lightroom also support the format. The Adobe Photoshop Express app for Android can open DNG files, too; the same one is available for iOS. You can open a Virtual Dongle Image file with the USB Dongle Backup and Recovery program from Soft-Key Solutions.
How to Convert a DNG File
If you’re already using a program that can open a DNG file, then you can probably also use it to convert it. Photoshop supports saving this format to a number of other file types like RAW, MPO, PXR, and PSD. For example, if you open the DNG file in Photoshop, go to File > Save As to pick a different format to save it to. Another option is to use a free file converter. One we often recommend is Zamzar, an online converter that can save to JPG, TIFF, BMP, GIF, PNG, TGA, etc., including PDF. Some of those programs listed above can also compress the file if you want to keep the format, but without the larger file size. Lightroom is one example: Right-click the file and go to Export > Export, choose DNG as the image format, pick Medium for the JPEG Preview setting, enable Use Lossy Compression, and resize the image as necessary.
File Still Doesn’t Open?
At this point, if after trying the above tools, your file isn’t opening correctly, take another look at the file extension. Many of them look very similar, even though the formats themselves aren’t at all related. In this case, a DNG opener won’t open your file. For example, DGN is the extension used for MicroStation Design 2D/3D drawing files—open one of those with MicroStation or Bentley View. DNH is a plain text script used by the game Touhou Danmakufu.