Comprehensive Guide to ZKTeco DAT File Readers: Reading Attendance Data

If you are an HR manager, a system administrator, or a business owner using ZKTeco biometric devices, you have likely encountered the .dat file extension. You download the logs from your device, eager to process payroll or check attendance, only to be met with a file that nothing on your computer seems to open.

The company network goes down. HR cannot "sync" the biometric devices to the main server.

For millions of HR managers, system administrators, and IT professionals, encountering a ZKTeco DAT file for the first time is a moment of frustration. You plug the USB drive into the device, download the "AttLog.dat" file, bring it to your computer, double-click it—and nothing happens. Your operating system doesn’t know what to do with it.

A common misconception is that "DAT file readers" are universal. They are not. The internal structure of a ZKTeco DAT file varies wildly depending on:

For IT administrators, reading the .dat file manually might be preferred. Since these are often structured text files, they can be parsed using:

the data into human-readable formats (Excel, CSV, PDF).

Create a parser to extract data from the .dat file. You might need to:

Because the .dat file only contains User IDs, you will need a master employee list. Use a VLOOKUP or XLOOKUP formula in Excel to automatically map the numeric User IDs to actual employee names. Method 3: Use Official ZKTeco Software

Keep in mind that this is a highly simplified example, and you'll need to adapt it to your specific use case.