Microsoft DOS debug command

Updated: 11/10/2017 by Computer Hope

About debug

Debug is a method of looking at portions of your computer and writing assembly code to perform certain tasks on your computer.


The debug command is an external command and is available in the below 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.

All Versions of MS-DOS
Windows 95
Windows 98
Windows ME
Windows NT
Windows 2000
Windows XP

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 Debug you need to "Q" and enter
To execute the Debug routine you need to do "G" and 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>

Additional information

  • Additional information about the above debug routine and other debug routines can be found on our debug routine page.
  • See our debug definition for further information and related links on this term.