Overview

i3 is a tiling window manager that arranges windows in a configurable tree rather than leaving placement to a conventional desktop. It suits advanced GNU/Linux and BSD users who want keyboard-driven control and are prepared to configure their environment. Its strongest case is flexible layouts and workspace handling; its X11 focus makes it the wrong fit for users seeking a window manager for another operating system or display system.

Key features

Windows can be split, stacked, or tabbed within a tree. That gives users several ways to organize a crowded screen, though the layout depends on learning and shaping the configuration rather than relying on a fixed preset. Workspaces group windows and can be associated with multiple screens, making it practical to keep tasks separated across monitors.

A configuration file controls key bindings, application startup, workspace assignments, and colors. This breadth is useful to developers and other advanced users who want a tailored workflow, but less appealing to anyone who would rather adjust settings through a graphical interface. Application rules and window grouping add control over how applications fit into that setup.

Multi-monitor support includes attaching or detaching displays during operation and rotated monitors. An inter-process communication interface accepts commands and supports event subscriptions, giving other software a way to interact with i3. The project describes integrations with i3bar, i3status, and external workspace bars such as dzen2; these options extend the setup, while adding components also means more choices to make.

Pricing

i3 is free and open source under the BSD license. Its free plan costs 0.00 USD per free and includes the window manager without a paid tier. There is no free trial because there is no paid plan to trial. This suits users who want a no-cost, openly licensed window manager; the trade-off is that i3 targets GNU/Linux and BSD on X11 rather than serving as a general-purpose choice across platforms.

Platforms

i3 targets GNU/Linux and BSD as an X11 window manager. Installation is recommended through packages from the user's distribution, with Debian and Ubuntu repositories also provided. Releases are cryptographically signed, and users are asked to verify them before installation. The current stable release is version 4.25.1, dated 2026-02-06. Questions can be directed to GitHub Discussions, IRC, or the mailing list.

Who it's for

i3 is best for advanced users and developers who value configurable layouts, workspace assignments, and multi-monitor handling enough to work with a file-based setup. It is a poor match for users who need a window manager outside GNU/Linux or BSD, or who do not use X11.

Pros and cons

Pros: Split, stacking, and tabbed layouts offer meaningful ways to organize windows in the same tree.
Pros: Workspaces can be grouped across multiple screens, with support for monitor changes and rotation.
Pros: Key bindings, startup behavior, workspace assignments, and colors are configurable, and the software is free under the BSD license.
Cons: Its X11 and GNU/Linux/BSD focus rules it out for users on other systems or display environments.
Cons: Configuration-file customization and its advanced-user focus put a learning and setup burden on people seeking a ready-made desktop workflow.

Alternatives

For more options, browse Window Management Software.

Choose awesome if you want a free Linux X window manager under the GNU GPLv2 license.
Qtile is another free, open-source Linux desktop window manager/compositor, under the MIT license.
Choose yabai if you need a free tiling window manager for macOS rather than i3's GNU/Linux and BSD target.
komorebi spans Windows and macOS and has a freemium model; its Windows single-platform license is 10.00 USD per month, billed monthly.
spectrwm is a free X11 window manager with Linux, macOS, and Windows platforms listed, under the ISC license.
bug.n is a free GPL-3.0 window manager for Windows.
Amethyst is a free, open-source macOS option with configurable layouts, keyboard shortcuts, and application floating or tiling rules.
DisplayFusion is a freemium Windows option with a free version after trial and a Pro Standard lifetime license at 34.00 USD per once, billed per machine.

Verdict

Choose i3 if you use GNU/Linux or BSD on X11 and want control over window layouts, workspaces, and monitor behavior without paying for the software. Its main reason to look elsewhere is its narrow platform and display-system focus; users who need macOS or Windows support should choose an alternative built for that system.

	i3	subtle
Free plan	Yes	No
Free trial	No	No
Paid from	Free	—
Open source	No	No
Platforms	Linux, self-hosted	Linux
Free plan	Yes	Yes
Platforms	linux	linux
Layout presets	Yes	—
Application rules	Yes	Yes
Window grouping	Yes	—
Virtual desktop controls	Yes	Yes

i3 vs subtle

i3

subtle