One very basic operation is opening a new terminal. By default, the keybinding for this is mod+Enter, that is Alt+Enter in the default configuration. By pressing mod+Enter, a new terminal will be opened. It will fill the whole space available on your screen.

If you now open another terminal, i3 will place it next to the current one, splitting the screen size in half. Depending on your monitor, i3 will put the created window beside the existing window (on wide displays) or below the existing window (rotated displays).

To move the focus between the two terminals, you can use the direction keys which you may know from the editor vi. However, in i3, your homerow is used for these keys (in vi, the keys are shifted to the left by one for compatibility with most keyboard layouts). Therefore, mod+J is left, mod+K is down, mod+L is up and mod+; is right. So, to switch between the terminals, use mod+K or mod+L. Of course, you can also use the arrow keys.

At the moment, your workspace is split (it contains two terminals) in a specific direction (horizontal by default). Every window can be split horizontally or vertically again, just like the workspace. The terminology is "window" for a container that actually contains an X11 window (like a terminal or browser) and "split container" for containers that consist of one or more windows.

TODO: picture of the tree

To split a window vertically, press mod+v. To split it horizontally, press mod+h.

A split container can have one of the following layouts:

To switch modes, press mod+e for default, mod+s for stacking and mod+w for tabbed.

To display a window in fullscreen mode or to go out of fullscreen mode again, press mod+f.

There is also a global fullscreen mode in i3 in which the client will span all available outputs.

Aside from opening applications from a terminal, you can also use the handy dmenu which is opened by pressing mod+d by default. Just type the name (or a part of it) of the application which you want to open. The corresponding application has to be in your $PATH for this to work.

Additionally, if you have applications you open very frequently, you can create a keybinding for starting the application directly. See the section [configuring] for details.

If an application does not provide a mechanism for closing (most applications provide a menu, the escape key or a shortcut like Control+W to close), you can press mod+Shift+q to kill a window. For applications which support the WM_DELETE protocol, this will correctly close the application (saving any modifications or doing other cleanup). If the application doesn’t support the WM_DELETE protocol your X server will kill the window and the behaviour depends on the application.

Workspaces are an easy way to group a set of windows. By default, you are on the first workspace, as the bar on the bottom left indicates. To switch to another workspace, press mod+num where num is the number of the workspace you want to use. If the workspace does not exist yet, it will be created.

A common paradigm is to put the web browser on one workspace, communication applications (mutt, irssi, …) on another one, and the ones with which you work, on the third one. Of course, there is no need to follow this approach.

If you have multiple screens, a workspace will be created on each screen at startup. If you open a new workspace, it will be bound to the screen you created it on. When you switch to a workspace on another screen, i3 will set focus to that screen.

To move a window to another workspace, simply press mod+Shift+num where num is (like when switching workspaces) the number of the target workspace. Similarly to switching workspaces, the target workspace will be created if it does not yet exist.

The easiest way to resize a container is by using the mouse: Grab the border and move it to the wanted size.

See [resizingconfig] for how to configure i3 to be able to resize columns/rows with your keyboard.

To restart i3 inplace (and thus get into a clean state if there is a bug, or to upgrade to a newer version of i3) you can use mod+Shift+r.

To cleanly exit i3 without killing your X server, you can use mod+Shift+e.

Floating mode is the opposite of tiling mode. The position and size of a window are not managed by i3, but by you. Using this mode violates the tiling paradigm but can be useful for some corner cases like "Save as" dialog windows, or toolbar windows (GIMP or similar). Those windows usually set the appropriate hint and are opened in floating mode by default.

You can toggle floating mode for a window by pressing mod+Shift+Space. By dragging the window’s titlebar with your mouse you can move the window around. By grabbing the borders and moving them you can resize the window. You can also do that by using the [floating_modifier].

For resizing floating windows with your keyboard, see [resizingconfig].

Floating windows are always on top of tiling windows.

The building blocks of our tree are so called Containers. A Container can host a window (meaning an X11 window, one that you can actually see and use, like a browser). Alternatively, it could contain one or more Containers. A simple example is the workspace: When you start i3 with a single monitor, a single workspace and you open two terminal windows, you will end up with a tree like this:

It is only natural to use so-called Split Containers in order to build a layout when using a tree as data structure. In i3, every Container has an orientation (horizontal, vertical or unspecified). So, in our example with the workspace, the default orientation of the workspace Container is horizontal (most monitors are widescreen nowadays). If you change the orientation to vertical (mod+v in the default config) and then open two terminals, i3 will configure your windows like this:

An interesting new feature of the tree branch is the ability to split anything: Let’s assume you have two terminals on a workspace (with horizontal orientation), focus is on the right terminal. Now you want to open another terminal window below the current one. If you would just open a new terminal window, it would show up to the right due to the horizontal workspace orientation. Instead, press mod+v to create a Vertical Split Container (to open a Horizontal Split Container, use mod+h). Now you can open a new terminal and it will open below the current one:

You probably guessed it already: There is no limit on how deep your hierarchy of splits can be.

Let’s stay with our example from above. We have a terminal on the left and two vertically split terminals on the right, focus is on the bottom right one. When you open a new terminal, it will open below the current one.

So, how can you open a new terminal window to the right of the current one? The solution is to use focus parent, which will focus the Parent Container of the current Container. In this case, you would focus the Vertical Split Container which is inside the horizontally oriented workspace. Thus, now new windows will be opened to the right of the Vertical Split Container:

It is possible and recommended to use comments in your configuration file to properly document your setup for later reference. Comments are started with a # and can only be used at the beginning of a line:

Examples:

i3 uses X core fonts (not Xft) for rendering window titles. You can use xfontsel(1) to generate such a font description. To see special characters (Unicode), you need to use a font which supports the ISO-10646 encoding.

If i3 cannot open the configured font, it will output an error in the logfile and fall back to a working font.

Syntax:

Examples:

A keyboard binding makes i3 execute a command (see below) upon pressing a specific key. i3 allows you to bind either on keycodes or on keysyms (you can also mix your bindings, though i3 will not protect you from overlapping ones).

My recommendation is: If you often switch keyboard layouts but you want to keep your bindings in the same physical location on the keyboard, use keycodes. If you don’t switch layouts, and want a clean and simple config file, use keysyms.

Syntax:

Examples:

Available Modifiers:

To move floating windows with your mouse, you can either grab their titlebar or configure the so called floating modifier which you can then press and click anywhere in the window itself to move it. The most common setup is to use the same key you use for managing windows (Mod1 for example). Then you can press Mod1, click into a window using your left mouse button, and drag it to the position you want.

When holding the floating modifier, you can resize a floating window by pressing the right mouse button on it and moving around while holding it. If you hold the shift button as well, the resize will be proportional.

Syntax:

Example:

New workspaces get a reasonable default orientation: Wide-screen monitors (anything wider than high) get horizontal orientation, rotated monitors (anything higher than wide) get vertical orientation.

With the default_orientation configuration directive, you can override that behaviour.

Syntax:

Example:

This option determines in which mode new containers on workspace level will start.

Syntax:

Example:

This option determines which border style new windows will have.

Syntax:

Example:

With the for_window command, you can let i3 execute any command when it encounters a specific window. This can be used to set windows to floating or to change their border style, for example.

Syntax:

Examples:

The valid criteria are the same as those for commands, see [command_criteria].

As you learned in the section about keyboard bindings, you will have to configure lots of bindings containing modifier keys. If you want to save yourself some typing and be able to change the modifier you use later, variables can be handy.

Syntax:

Example:

Variables are directly replaced in the file when parsing. There is no fancy handling and there are absolutely no plans to change this. If you need a more dynamic configuration you should create a little script which generates a configuration file and run it before starting i3 (for example in your ~/.xsession file).

Specific windows can be matched by window class and/or window title. It is recommended that you match on window classes instead of window titles whenever possible because some applications first create their window, and then worry about setting the correct title. Firefox with Vimperator comes to mind. The window starts up being named Firefox, and only when Vimperator is loaded does the title change. As i3 will get the title as soon as the application maps the window (mapping means actually displaying it on the screen), you’d need to have to match on Firefox in this case.

You can prefix or suffix workspaces with a ~ to specify that matching clients should be put into floating mode. If you specify only a ~, the client will not be put onto any workspace, but will be set floating on the current one.

Syntax:

Examples:

Note that the arrow is not required, it just looks good :-). If you decide to use it, it has to be a UTF-8 encoded arrow, not -> or something like that.

By using the exec keyword outside a keybinding, you can configure which commands will be performed by i3 on initial startup. exec commands will not run when restarting i3, if you need a command to run also when restarting i3 you should use the exec_always keyword. These commands will be run in order.

Syntax:

Examples:

If you assign clients to workspaces, it might be handy to put the workspaces on specific screens. Also, the assignment of workspaces to screens will determine which workspace i3 uses for a new screen when adding screens or when starting (e.g., by default it will use 1 for the first screen, 2 for the second screen and so on).

Syntax:

The output is the name of the RandR output you attach your screen to. On a laptop, you might have VGA1 and LVDS1 as output names. You can see the available outputs by running xrandr --current.

Examples:

You can change all colors which i3 uses to draw the window decorations.

Syntax:

Where colorclass can be one of:

You can also specify the color to be used to paint the background of the client windows. This color will be used to paint the window on top of which the client will be rendered.

Syntax:

Only clients that do not cover the whole area of this window expose the color used to paint it. If you use a color other than black for your terminals, you most likely want to set the client background color to the same color as your terminal program’s background color to avoid black gaps between the rendered area of the termianal and the i3 border.

Colors are in HTML hex format (#rrggbb), see the following example:

Examples (default colors):

Note that for the window decorations, the color around the child window is the background color, and the border color is only the two thin lines at the top of the window.

i3 uses unix sockets to provide an IPC interface. This allows third-party programs to get information from i3, such as the current workspaces (to display a workspace bar), and to control i3.

The IPC socket is enabled by default and will be created in /tmp/i3-%u/ipc-socket.%p where %u is your UNIX username and %p is the PID of i3.

You can override the default path through the environment-variable I3SOCK or by specifying the ipc-socket directive. This is discouraged, though, since i3 does the right thing by default.

Examples:

You can then use the i3-msg application to perform any command listed in the next section.

If you have a setup where your mouse usually is in your way (like a touchpad on your laptop which you do not want to disable completely), you might want to disable focus follows mouse and control focus only by using your keyboard. The mouse will still be useful inside the currently active window (for example to click on links in your browser window).

Syntax:

Example:

When you are in fullscreen mode, some applications still open popup windows (take Xpdf for example). This is because these applications may not be aware that they are in fullscreen mode (they do not check the corresponding hint). There are two things which are possible to do in this situation:

Syntax:

Example:

When being in a tabbed or stacked container, the first container will be focused when you use focus down on the last container — the focus wraps. If however there is another stacked/tabbed container in that direction, focus will be set on that container. This is the default behaviour so you can navigate to all your windows without having to use focus parent.

If you want the focus to always wrap and you are aware of using focus parent to switch to different containers, you can use the force_focus_wrapping configuration directive. After enabling it, the focus will always wrap.

Syntax:

Example:

The split command makes the current window a split container. Split containers can contain multiple windows. Every split container has an orientation, it is either split horizontally (a new window gets placed to the right of the current one) or vertically (a new window gets placed below the current one).

If you apply this command to a split container with the same orientation, nothing will happen. If you use a different orientation, the split container’s orientation will be changed (if it does not have more than one window).

Syntax:

Example:

Use layout default, layout stacking or layout tabbed to change the current container layout to default, stacking or tabbed layout, respectively.

To make the current window (!) fullscreen, use fullscreen, to make it floating (or tiling again) use floating enable respectively floating disable (or floating toggle):

Examples:

To change the focus, use the focus command: focus left, focus right, focus down and focus up.

There are a few special parameters you can use for the focus command:

For moving, use move left, move right, move down and move up.

Examples:

To change to a specific workspace, use the workspace command, followed by the number or name of the workspace. To move containers to specific workspaces, use move workspace.

You can also switch to the next and previous workspace with the commands workspace next and workspace prev, which is handy, for example, if you have workspace 1, 3, 4 and 9 and you want to cycle through them with a single key combination.

To move a container to another xrandr output such as LVDS1 or VGA1, you can use the move output command followed by the name of the target output. You may also use left, right, up, down instead of the xrandr output name to move to the the next output in the specified direction.

Examples:

If you want to resize containers/windows using your keyboard, you can use the resize command:

Syntax:

Direction can be one of up, down, left or right. The optional pixel argument specifies by how many pixels a floating container should be grown or shrinked (the default is 10 pixels). The ppt argument means percentage points and specifies by how many percentage points a tiling container should be grown or shrinked (the default is 10 percentage points).

I recommend using the resize command inside a so called mode:

Often when in a multi-monitor environment, you want to quickly jump to a specific window. For example, while working on workspace 3 you may want to jump to your mail client to email your boss that you’ve achieved some important goal. Instead of figuring out how to navigate to your mailclient, it would be more convenient to have a shortcut. You can use the focus command with criteria for that.

Syntax:

Examples:

This feature is like the jump feature: It allows you to directly jump to a specific window (this means switching to the appropriate workspace and setting focus to the windows). However, you can directly mark a specific window with an arbitrary label and use it afterwards. You do not need to ensure that your windows have unique classes or titles, and you do not need to change your configuration file.

As the command needs to include the label with which you want to mark the window, you cannot simply bind it to a key. i3-input is a tool created for this purpose: It lets you input a command and sends the command to i3. It can also prefix this command and display a custom prompt for the input dialog.

Syntax:

Example (in a terminal):

To change the border of the current client, you can use border normal to use the normal border (including window title), border 1pixel to use a 1-pixel border (no window title) and border none to make the client borderless.

There is also border toggle which will toggle the different border styles.

Examples:

You can make i3 reload its configuration file with reload. You can also restart i3 inplace with the restart command to get it out of some weird state (if that should ever happen) or to perform an upgrade without having to restart your X session. To exit i3 properly, you can use the exit command, however you don’t need to (simply killing your X session is fine as well).

Examples:

To help you get going if you have never used multiple monitors before, here is a short overview of the xrandr options which will probably be of interest to you. It is always useful to get an overview of the current screen configuration. Just run "xrandr" and you will get an output like the following:

Several things are important here: You can see that LVDS1 is connected (of course, it is the internal flat panel) but VGA1 is not. If you have a monitor connected to one of the ports but xrandr still says "disconnected", you should check your cable, monitor or graphics driver.

The maximum resolution you can see at the end of the first line is the maximum combined resolution of your monitors. By default, it is usually too low and has to be increased by editing /etc/X11/xorg.conf.

So, say you connected VGA1 and want to use it as an additional screen:

This command makes xrandr try to find the native resolution of the device connected to VGA1 and configures it to the left of your internal flat panel. When running "xrandr" again, the output looks like this:

Please note that i3 uses exactly the same API as xrandr does, so it will see only what you can see in xrandr.

See also [presentations] for more examples of multi-monitor setups.

There are several things to configure in i3 which may be interesting if you have more than one monitor:

A very common thing amongst users of exotic window managers is a status line at some corner of the screen. It is an often superior replacement to the widget approach you have in the task bar of a traditional desktop environment.

If you don’t already have your favorite way of generating such a status line (self-written scripts, conky, …), then i3status is the recommended tool for this task. It was written in C with the goal of using as few syscalls as possible to reduce the time your CPU is woken up from sleep states. Because i3status only spits out text, you need to combine it with some other tool, like i3bar. Use a pipe to connect them: i3status | i3bar -d.

Regardless of which application you use to display the status line, you want to make sure that it registers as a dock window using EWMH hints. i3 will position the window either at the top or at the bottom of the screen, depending on which hint the application sets. With i3bar, you can use -d or -dbottom for positioning it at the bottom and -dtop to position it at the top of the screen.

When giving a presentation, you typically want the audience to see what you see on your screen and then go through a series of slides (if the presentation is simple). For more complex presentations, you might want to have some notes which only you can see on your screen, while the audience can only see the slides.