Starts a separate Command Prompt window to run a specified program or command.


start ["title"] [/d <path>] [/i] [{/min | /max}] [{/separate | /shared}] [{/low | /normal | /high | /realtime | /abovenormal | /belownormal}] [/node <NUMA node>] [/affinity <hexaffinity>] [/wait] [/b] [/machine <x86|amd64|arm|arm64>] [<command> [<parameter>... ] | <program> [<parameter>... ]]


The machine parameter is currently in PREVIEW for Windows 11 only. The parameter is available beginning with the Windows 11 Insider Preview Build 22557. This information relates to a prerelease product that may be substantially modified before it's released. Microsoft makes no warranties, expressed or implied, with respect to the information provided here.


Parameter Description
<"title"> Specifies the title to display in the Command Prompt window title bar.
/d <path> Specifies the startup directory.
/i Passes the Cmd.exe startup environment to the new Command Prompt window. If /i isn't specified, the current environment is used.
{/min \| /max} Specifies to minimize (/min) or maximize (/max) the new Command Prompt window.
{/separate \| /shared} Starts 16-bit programs in a separate memory space (/separate) or shared memory space (/shared). These options aren't supported on 64-bit platforms.
{/low \| /normal \| /high \| /realtime \| /abovenormal \| /belownormal} Starts an application in the specified priority class.
/node <NUMA node> Specifies the preferred Non-Uniform Memory Architecture (NUMA) node as a decimal integer.
/affinity <hexaffinity> Applies the specified processor affinity mask (expressed as a hexadecimal number) to the new application.
/wait Starts an application and waits for it to end.
/b Starts an application without opening a new Command Prompt window. CTRL+C handling is ignored unless the application enables CTRL+C processing. Use CTRL+BREAK to interrupt the application.
/machine <x86\|amd64\|arm\|arm64> Specifies the machine architecture of the application process.
[<command> [<parameter>... ] \| <program> [<parameter>... ]] Specifies the command or program to start.
<parameter> Specifies parameters to pass to either the command or the program.
/? Displays help at the command prompt.


  • You can run non-executable files through their file association by typing the name of the file as a command.

  • If you run a command that contains the string CMD as the first token without an extension or path qualifier, CMD is replaced with the value of the COMSPEC variable. This prevents users from picking up cmd from the current directory.

  • If you run a 32-bit graphical user interface (GUI) application, cmd doesn't wait for the application to quit before returning to the command prompt. This behavior doesn't occur if you run the application from a command script.

  • If you run a command that uses a first token that isn't a command or the file path to an existing file with an extension, Cmd.exe uses the value of the PATHEXT environment variable to determine which extensions to look for and in what order. The default value for the PATHEXT variable is .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC

    Note the syntax is the same as the PATH variable, with semicolons (;) separating each extension.

  • start searches for a specified executable file, and if found the executable will launch regardless of the current working directory. When searching for an executable file, if there's no match on any extension, start checks to see if the name matches a directory name. If it does, start opens Explorer.exe on that path.


To start the Myapp program at the command prompt and retain use of the current Command Prompt window, type:

start Myapp

To view the start command-line help topic in a separate maximized Command Prompt window, type:

start /max start /?