Modifier Keys Usage Frequency

By Xah Lee. Date: . Last updated: .

This info is important for those who design keymaps that need to work on both Mac and Microsoft Windows, or Linux.

When you design a keyboard layout, such as in a Do It Yourself keyboard like Gergo

You have the question of where to place the modifier keys, namely the ❖ Window Ctrl Alt. They need to be optimal for using any of {Mac, Windows, Linux}.

For Windows and Linux, their modifier key use is the same. So the question is really about just Windows and Mac.

Key Equivalence

First, note that:

However, ⌥ option and Alt are the same key. They send the same electric signal. It's just labeling difference.

Also, ⌘ command and ❖ Window are the same key. It's just labeling difference.

So, for our purpose, we can just use the notation ❖ Window Alt.

[see Difference Between Apple and Microsoft keyboards]

Modifier Keys Usage Frequency

Order of importance of the modifier keys.

On the Mac, the ❖ Window is the most used. Ctrl Alt are rare, except used together with ❖ Window. The Alt is frequently used if you use text editor. It is used to move cursor by word.

on Windows, the distribution of usage is much more even.


Optimal Placement for Modifier Keys

In general, you want to place the most frequently used function to most easy to press key spots.

This means, depending on whether you use Mac or Windows, you need different placement of modifier keys.

This means, you need to do this swap when switching from Mac to Windows:



This means, ideally, your keyboard should have 2 modes. One for Mac, one for Windows. This makes it more complex. Because now you need to switch keyboard mode whenever you use the keyboard on Mac or Windows.

Generic Fixed Placement of Modifier Keys

Alternatively, you can design a fixed layout, that works ok for both Mac and Windows. This may not be the most optimal, but, reduce complexity if you need to switch between Mac and Windows often.

For a fixed layout, ideally, we can simply place all 3 keys on 3 most easy to press keyspots. But, in real world, you don't have 3 easy spots available, regardless what kinda of ergo Do It Yourself keyboard design you have.

So, what we can do is to pick 2 modifier keys and place them both on easy spots.

So, for Mac, ❖ Window is critical. you need that on a easy spot for sure. Then, Ctrl is also critical, because it is the primary keyboard shortcut modifier for Windows.

So, we need both ❖ Window Ctrl to be on easy spots. But also, on Windows, Alt is frequently used for Alt+Tab. (on Microsoft Windows 10, ❖ Window+Tab can replace it.) This means, Alt can be in somewhat less easy spot.

Keybinding and Input-System