MS-DOS and Windows command line debug command

Updated: 06/22/2018 by Computer Hope
Debug command entered at a command line C prompt.

The debug command is used to look at portions of your computer and write assembly code to perform certain tasks on your computer.


Debug is an external command and is available for the following Microsoft operating systems. MS-DOS 2.x - 4.x use as the external file. MS-DOS 5.x and later and all versions of Windows that support this command above uses debug.exe as the external file.

Debug syntax

DEBUG [[drive:][path]filename [testfile-parameters]]
[drive:][path]filename Specifies the file you want to test.
testfile-parameters Specifies command line information required by the file you want to test.

After debug starts, type "?" to display a list of debugging commands.

To get out of debugging mode, you need to type "Q" and press Enter.
To execute the debug routine, you need to type "G" and press Enter.

Debug examples

debug      <press Enter>
-D40:00 <TypeD40:00, and press Enter>

Information about your computer ports is displayed.

-Q        <Type Q, and press enter>