# window_id

Source: https://libtmux.org/en/tmux/3.2a/catalog/formats/window_id/

> Unique window ID

format variable tmux3.2a

Unique window ID

* Scope

  Describes the window being formatted

* Type

  Text

* Usage

  `#{window_id}`

## Description[#](https://libtmux.org/en/tmux/3.2a/catalog/formats/window_id/#description)

Unique window ID

## Releases[#](https://libtmux.org/en/tmux/3.2a/catalog/formats/window_id/#releases)

* [tmux 3.7c](https://libtmux.org/en/tmux/3.7c/catalog/formats/window_id/) : present
* [tmux 3.2a](https://libtmux.org/en/tmux/3.2a/catalog/formats/window_id/) : present

## Source[#](https://libtmux.org/en/tmux/3.2a/catalog/formats/window_id/#source)

* Defined in

  [`format.c:2930`](https://github.com/tmux/tmux/blob/3b929f332aafa7f1080eacc31feb11ffbb1d1841/format.c#L2930)

* C source reference

  [`format_cb_window_id`](https://libtmux.org/en/tmux/3.2a/reference/c-function-format-c-format_cb_window_id/)

* CLI Manual

  [Original manual entry](https://libtmux.org/en/tmux/3.2a/manual/full/#window_id)

## Used by[#](https://libtmux.org/en/tmux/3.2a/catalog/formats/window_id/#used-by)

Library documentation that names this format variable.

* Python

  [`libtmux_mcp.tools.pane_tools.respawn_pane`](https://libtmux.org/en/py/latest/mcp/reference/libtmux_mcp-tools-pane_tools-respawn_pane/), [`libtmux_mcp.tools.session_tools.select_window`](https://libtmux.org/en/py/latest/mcp/reference/libtmux_mcp-tools-session_tools-select_window/), [`libtmux_mcp.tools.window_tools.get_window_info`](https://libtmux.org/en/py/latest/mcp/reference/libtmux_mcp-tools-window_tools-get_window_info/), [`libtmux_mcp.tools.window_tools.kill_window`](https://libtmux.org/en/py/latest/mcp/reference/libtmux_mcp-tools-window_tools-kill_window/), [`libtmux_mcp.tools.window_tools.rename_window`](https://libtmux.org/en/py/latest/mcp/reference/libtmux_mcp-tools-window_tools-rename_window/), [`libtmux.Client`](https://libtmux.org/en/py/latest/reference/libtmux-client/) and 10 more

* Go

  [`tmux.FormatValues.WindowID`](https://libtmux.org/en/go/latest/reference/tmux-formatvalues-windowid/)