Dat files are one of the greatest mysteries of Windows: why are their icons blank? Why can’t you open them? What’s their purpose? Sometimes .dat files should be left as they are because they contain vital data related to a piece of software that’s best not tampered with.

But other times .dat files can actually be media files, email files, or other file types that Windows or a given software has failed to define for some reason. In these situations .dat files can actually be opened.

Here we’re going to show you how to check what’s really contained in a .dat file and how to convert it in the rare case you need to.

What is a .dat File?

By default, .dat files don’t associate with any particular program, and they shouldn’t because the data they contain is often binary and undecipherable. However, if you want to open any DAT file, then the most universal way is to use Notepad (or, preferably, a more advanced text editor like Notepad++, which displays the internal file information far more clearly).

The main indicator of what a given .DAT file does and what software it’s attached to is, naturally, to be found in its name and the name of its directory. In the below example I can see that this particular DAT file I opened a moment ago contains audio data for the game Super Meat Boy. There’s a reason for it being there and no reason to tamper with it.

Most of the time when you open a .DAT file in Notepad (or Notepad++ in our case), it will look something like the following image.

There’s really nothing you can do with data like this except potentially mess up whatever software it’s connected to by changing something. If this is what you see inside a .DAT file, then just back out for now.

In other situations you may even be blocked from opening the .DAT file in a text editor because it’s a system file and protected by Windows.

If, however, you’re suspicious of where the DAT file came from or its purpose, you can always run a scan on the file using an antivirus app. Because they’re generic and not easily opened, .DAT files are often used as a convenient hiding place for malware.

Some .DAT files actually have easily readable, clear information inside them. This one I opened in a folder for an old MMO game contains data relating to my online account for that game.

Again, don’t tamper with it unless you know what you’re doing, but the point is that sometimes there may be useful and readable stuff in a .dat file.

Convert .DAT Files to Other Formats

In some cases, if you’re sure you know the source of your DAT file (such as whether it was a video file), you can try to open .DAT in other formats, such as audio or video.

VCD files (which use the .mpg format), for example, can end up stored in the .dat format.

In a case like this you can just right-click the .dat file, click Properties, then replace the “.dat” in its name with “.mpg” or whatever format you believe the original file was in. We strongly recommend doing this on a copy of the original .dat file, rather the original, because it could break the file.

When you’re done, click OK, and the .dat file will be in a media format and will, with a bit of luck, actually work.

Conclusion

For the most part, .dat files are a byword for a vast, diverse range of software-critical files that aren’t to be tinkered and tampered with. They’re obscured for a reason and normally contain complex piles of binary data that isn’t readily modifiable.

But if you believe that a given .dat file contains some kind of playable media, which is sometimes possible, then create a copy and by all means play around with it to see if you can open it in the relevant format. But we stress again, tinker around on a copy, not the original file.

Content Manager at Make Tech Easier. Enjoys Android, Windows, and tinkering with retro console emulation to breaking point.

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