Amethyst has been tiling windows on the Mac for longer than most of its competitors have existed, and it is still free, still maintained and still the easiest tiling window manager to get running. It is also the one most likely to feel subtly broken for a day until you change one macOS setting. Here is what it does and what it leaves alone.
The short answer
Amethyst is the tiling window manager to try first. It installs in one Homebrew command, works on macOS versions nothing else supports, costs nothing forever, and needs no config file to be useful. Try AeroSpace instead if you want i3 style workspaces and a text configuration you can keep in your dotfiles.
What Amethyst is
The project describes itself as a “tiling window manager for macOS along the lines of xmonad”. Windows are placed automatically according to whichever layout is active, and you switch layouts, move windows between positions and jump between screens with keyboard shortcuts. The reference to xmonad is a fair one: like xmonad, the appeal is that a sensible arrangement happens without you asking, and the mouse becomes optional rather than required.
| Price | Free, and the maintainer states it always will be |
|---|---|
| Licence | MIT, open source |
| Minimum macOS | macOS 10.15 and later |
| Install | brew install --cask amethyst, or a download from the releases page |
| Layouts | Tall, Wide, Fullscreen, Column, Row, binary space partitioning, Floating and others |
| Configuration | Graphical preferences, optional YAML file, custom JavaScript layouts in beta |
| Permissions needed | Accessibility, under Privacy and Security |
| Requires disabling SIP | No mention of SIP anywhere in its documentation |
| Restores a saved layout | Not documented |
The setting you have to change
Amethyst's documentation asks you to turn off Automatically rearrange Spaces based on most recent usein Mission Control settings. This is worth doing before you form an opinion about the app, because with it left on macOS silently reorders your Spaces behind your back, and every keyboard shortcut that means “go to the third workspace” starts landing somewhere unpredictable. People routinely conclude the app is buggy when what they are fighting is macOS.
It is the same setting implicated in a different problem elsewhere on this site: it is one of the two Mission Control settings involved in windows moving when you unplug a monitor. macOS has strong opinions about Spaces and they are not always yours.
Amethyst compared to the other free tilers
| Amethyst | Easiest to start. Widest macOS support at 10.15+. Graphical preferences. Uses real macOS Spaces. |
|---|---|
| AeroSpace | i3 style tree tiling with its own emulated workspaces. TOML config. macOS 13+. Still public beta. |
| yabai | Most powerful and fully scriptable, driven from the command line. Its advanced features document partially disabling System Integrity Protection. |
All three are free and MIT licensed, so trying them costs an afternoon rather than money. The practical ordering for most people is Amethyst first because it asks least of you, AeroSpace if you want workspaces done properly, and yabai if you have decided the SIP trade is acceptable.
What Amethyst does not do
It does not remember an arrangement
Amethyst's documentation covers no saving or restoring of layouts and does not address what happens when a display connects or disconnects. Like every tiler, it computes an arrangement from the windows in front of it. Pull a monitor out and it will tile what remains, neatly and immediately. What it cannot do is put back the specific arrangement you had built, because that arrangement was an output of its algorithm rather than a thing it stored.
It does not snap the window in your hand
Tiling is automatic placement, which is a different feeling from dragging a window to an edge and having it fill half the screen. If the latter is what you are after, macOS does it built in and Rectangle does it with more layouts, free.
Where Putback fits, honestly
We make Putback, so weigh this accordingly. It is not a tiling window manager and not an Amethyst replacement. It watches where your windows end up as you work, keeps a separate memory for each display setup, and restores everything when your displays change. It never places a window on its own initiative, so it sits alongside a tiler rather than fighting it.
If Amethyst's automatic tiling is all you need, you do not need us. The overlap is floating windows and the arrangements that reflect a decision rather than a rule. The whole category map, including snappers, switchers and restorers, is in the Mac window manager comparison.
