How to Open DAT File: Step-by-Step Guide to View & Convert DAT File in 2026

DAT files are one of the most frustrating file types you’ll encounter. You double-click, and nothing happens. Your computer doesn’t know what to do with them. This guide will show you exactly how to open DAT files, identify what type of data they contain, and convert them into usable formats.

What Is a DAT File?

A DAT file is a generic data file that stores information in plain text, binary, or proprietary formats. The .dat extension doesn’t tell you what program created the file or what’s inside it. Think of it as a box with no label. The contents could be anything: video, text, game data, email attachments, or configuration settings.

Different programs use DAT files for different purposes:

Common DAT file types include:

• Video files from VCD (Video CD) players
• Email attachments from Outlook (winmail.dat)
• Game data and saved game files
• Configuration files for software applications
• Database information
• Registry backup files

The challenge is that DAT files have no standard format. A DAT file from one program won’t open in another program, even though they share the same extension.

How to Identify What Type of DAT File You Have

Before you can open a DAT file, you need to figure out what created it. Here’s how to identify your DAT file type:

Check the File Location

Where you found the DAT file gives you important clues:

Email attachment: If the file is called winmail.dat, it came from Microsoft Outlook. This contains formatting and attachments from emails sent by Outlook users.

Program folder: DAT files inside application folders (like C:\Program Files) usually contain configuration data or game information specific to that program.

CD or DVD: DAT files on optical media are typically video files in VCD format.

Desktop or Downloads: These could be anything. You’ll need to investigate further.

Examine the File with a Text Editor

Open the DAT file in Notepad (Windows) or TextEdit (Mac) to peek inside:

1. Right-click the DAT file
2. Select “Open with”
3. Choose Notepad or TextEdit
4. Look at the first few lines

What you might see:

If you see readable text with formatting codes, it’s probably a text-based configuration file.

If you see complete gibberish or strange symbols, it’s likely binary data (video, audio, or encrypted information).

If you see HTML tags, it might be web-related data.

Check the File Header

The first few bytes of a file contain a signature that identifies the file type. You can use a hex editor or online tools to read these bytes:

• RIFF indicates a video or audio file
• %PDF means it’s actually a PDF
• PK suggests a ZIP archive
• MZ indicates an executable file

Understanding the header helps you rename the file with the correct extension.

How to Open DAT Files: Step-by-Step Methods

Method 1: Open with the Program That Created It

The most reliable way to open a DAT file is using the program that created it.

Steps:

1. Recall where you got the DAT file
2. If it came from a specific program, launch that program
3. Use the program’s “Open” or “Import” function
4. Navigate to the DAT file and open it

Example: If you exported data from a database program, open that same database program and import the DAT file.

Method 2: Try Common Programs Based on File Type

Different DAT file types respond to different programs. Here’s what to try:

For Video DAT Files (VCD Format)

VCD DAT files contain MPEG video data. Try these players:

VLC Media Player (recommended):

1. Download VLC from videolan.org
2. Install and launch VLC
3. Drag the DAT file into VLC
4. The video should play immediately

Other options: Windows Media Player, MPlayer, or any media player that supports MPEG format.

For Winmail.dat Files (Email Attachments)

When someone sends you an email from Outlook with formatting or attachments, you might receive winmail.dat instead of the actual files.

Online solution:

1. Visit winmaildat.com
2. Upload your winmail.dat file
3. Download the extracted attachments

Desktop solution:

1. Download Winmail Opener (free for Windows)
2. Install and run the program
3. Open your winmail.dat file
4. Extract the embedded files

For Game DAT Files

Game DAT files contain saved game data, character information, or game assets.

Steps:

1. Launch the game that created the file
2. Look for “Load Game” or “Import” options
3. Navigate to the DAT file location
4. Load the file through the game interface

Don’t edit game DAT files unless you know what you’re doing. Corruption can destroy your saved games.

For Configuration DAT Files

Some programs store settings in DAT files.

To view:

1. Open the file in Notepad
2. Read the settings (don’t edit unless necessary)
3. Save changes carefully if you make modifications

Backup the original DAT file before making any changes.

Method 3: Convert DAT Files to Usable Formats

If you can’t open the DAT file directly, converting it to a standard format often works.

Converting Video DAT Files

Using VLC Media Player:

1. Open VLC Media Player
2. Click “Media” then “Convert/Save”
3. Add your DAT file
4. Click “Convert/Save” at the bottom
5. Choose output format (MP4, AVI, etc.)
6. Select destination folder
7. Click “Start”

VLC will convert your DAT file to a standard video format that plays anywhere.

Converting Text DAT Files

If your DAT file contains readable text:

1. Open it in Notepad
2. Review the content
3. Click “File” then “Save As”
4. Change the extension to .txt
5. Save the file

Now you have a standard text file you can open anywhere.

Method 4: Change the File Extension

Sometimes a DAT file is actually another file type with the wrong extension. This happens when files are saved incorrectly or transmitted through systems that strip extensions.

How to change extensions safely:

Windows:

1. Open File Explorer
2. Click “View” tab
3. Check “File name extensions”
4. Right-click your DAT file
5. Select “Rename”
6. Change .dat to the suspected extension (.mp4, .pdf, .jpg, etc.)
7. Press Enter and confirm the warning

Mac:

1. Right-click the DAT file
2. Select “Get Info”
3. Expand “Name & Extension”
4. Change the extension
5. Confirm the change

Common extension replacements to try:

• .mp4 or .avi for video files
• .jpg or .png for images
• .txt for text documents
• .pdf for documents
• .zip for compressed files

Test the file after each change. If it doesn’t work, change it back and try another extension.

Troubleshooting Common DAT File Issues

The File Won’t Open in Any Program

Solutions:

Check if the file is corrupted by looking at its size. A 0 KB file is definitely corrupted.

Try opening it in a hex editor to see if there’s any data inside.

Search online for the specific filename (like “config.dat game name”) to find program-specific solutions.

Multiple DAT Files in One Folder

Some programs split data across multiple DAT files. You usually need to open the main program rather than the DAT files directly.

Look for a .exe file or main program file in the same folder. Launch that instead.

The DAT File Opens But Shows Garbage

This means you’re using the wrong program. The file is likely binary data that requires specific software to decode.

Go back to identifying the file type using the methods above.

Security Warning When Opening DAT Files

DAT files can contain executable code. Only open DAT files from trusted sources.

Scan the file with antivirus software before opening.

Never run .exe files that were disguised as .dat files unless you’re certain they’re safe.

Tools and Software for Opening DAT Files

Here’s a quick reference table of the best tools for different DAT file types:

File Type	Best Tool	Platform	Cost
Video DAT (VCD)	VLC Media Player	Windows, Mac, Linux	Free
Winmail.dat	Winmail Opener	Windows	Free
Winmail.dat	TNEF’s Enough	Mac	Free
Text DAT	Notepad/TextEdit	Windows/Mac	Free
Binary DAT	HxD Hex Editor	Windows	Free
Game DAT	Original game software	Varies	Varies
Database DAT	Original database program	Varies	Varies

Advanced: Using Command Line to Inspect DAT Files

For technical users, command line tools provide deeper insight into DAT files.

Windows Command Prompt:

type filename.dat

This displays the contents as text. Press Ctrl+C to stop if it’s binary garbage.

Linux or Mac Terminal:

file filename.dat

This command identifies the file type based on its content, regardless of extension.

head -n 20 filename.dat

This shows the first 20 lines of the file.

How to Prevent DAT File Problems

Best practices:

Keep track of where DAT files come from. Note the program or source when you download or receive them.

Don’t rename files to .dat unless you have a specific reason. Use proper extensions.

Backup important DAT files before attempting to open or modify them.

Use file management software that displays file types and headers, not just extensions.

When saving files, choose standard formats over proprietary DAT formats when possible.

Frequently Asked Questions

Are DAT files safe to open?

DAT files themselves are not inherently dangerous, but they can contain harmful code if they come from untrusted sources. Always scan DAT files with antivirus software before opening them, especially if you received them via email or download from unknown websites. Never execute a DAT file that claims to be a program unless you’re absolutely certain of its origin.

Can I delete DAT files from my computer?

It depends on what the DAT file contains. System DAT files and program configuration DAT files should not be deleted, as they can break software or cause system issues. Email winmail.dat files can be safely deleted after you extract their contents. Game DAT files that contain saved games should only be deleted if you no longer want those saves. When in doubt, move the DAT file to a backup folder instead of deleting it permanently.

Why do I keep receiving winmail.dat files in emails?

You receive winmail.dat files when someone sends you an email from Microsoft Outlook using Rich Text Format (RTF), but your email client doesn’t support this format. The sender’s Outlook packages all attachments and formatting into a winmail.dat container. To fix this, ask the sender to change their Outlook settings to send emails in HTML or Plain Text format instead of RTF. This prevents the winmail.dat problem entirely.

Can I convert a DAT file to MP4 permanently?

Yes, if the DAT file is actually a video file (like those from VCDs). Use VLC Media Player’s convert function to permanently change the DAT file to MP4 format. Once converted, you can delete the original DAT file and use the MP4 file on any device. The conversion process re-encodes the video, so there may be slight quality changes depending on your conversion settings.

What’s the difference between a DAT file and a DATA file?

Both .dat and .data extensions serve similar purposes, indicating generic data files. There’s no technical difference between them. Different programs use different naming conventions, but both indicate files containing program-specific information. The same identification and opening methods apply to both file types. Focus on the file’s origin and contents rather than whether it’s called .dat or .data.

Conclusion

Opening DAT files requires detective work. First, identify what created the file by checking its location, examining its contents in a text editor, or analyzing its header. Then, use the appropriate tool: VLC for video DAT files, Winmail Opener for email attachments, the original program for configuration or game files, or a simple rename for misidentified file types.

Most DAT file problems come from not knowing the file’s origin. When you download or receive a DAT file, note where it came from and what program created it. This information makes opening the file straightforward instead of frustrating.

Keep your file management organized, backup important DAT files before modifying them, and use trusted tools like VLC Media Player for conversions. With these strategies, you’ll handle DAT files confidently instead of being stuck wondering what’s inside that mysterious file.