June 2026

What is system-wide autocomplete on Mac?

System-wide autocomplete predicts the rest of what you're typing — in every app, not just one editor. As you write, a greyed suggestion appears at your cursor. Press Tab and it's yours.

Not a snippet expander, not word prediction

The phrase gets used loosely, so it's worth being precise. System-wide autocomplete means full-sentence prediction that works across the whole operating system — your mail client, your chat app, your notes, your browser. That's different from a text expander, where you type a trigger like addrand it pastes a saved block you wrote earlier. And it's different from word-level predictive text, which suggests one word at a time and only in some apps. System-wide autocomplete predicts prose you never typed before, everywhere you type.

How it works, step by step

The mechanism is the same no matter which app you're in, because it doesn't depend on the app cooperating. There are four moving parts:

1. Reading your text.macOS exposes focused text fields through the Accessibility API — the same system VoiceOver uses. MacAutocomplete reads the text before your cursor (the prefix) so it knows what you're in the middle of saying. Password and secure-input fields are never read.

2. Predicting the rest. That prefix goes to a local model running on Apple Silicon via MLX. It generates a likely continuation — a phrase, a clause, the end of your sentence.

3. Showing the ghost. The prediction is drawn in grey, inline, right after your caret — never replacing what you typed. Mid-sentence it looks like this:

Just confirming our call for Thursday at 2 — let me know if that still works for you.

4. Accepting it. Press ⇥ Tab or → to drop the whole suggestion into the field. Keep typing and it disappears — your next keystroke always wins, instantly, with nothing to dismiss.

It runs entirely on your Mac

Because everything happens on-device, there is zero outbound network for completions — you can confirm that yourself with Little Snitch. Nothing you type leaves the Mac, which matters when the "every app" promise includes your email drafts and private messages. It's also why the ghost appears in the time it takes to glance at it: there's no server round trip to wait on.

Where it works — and where it doesn't

Standard macOS text fields are fully supported: Mail, Slack, Notes, Messages, most browsers, and most chat apps. A few surfaces draw their own text on a canvas and don't expose it through the Accessibility API — Google Docs and Sheets, some GPU-based editors, and games. We'd rather be honest about the dead zones than pretend they don't exist. See the full picture of where it works across every app, and the detail of the Tab-to-accept gesture.

How it compares