AI Polish with Apple Intelligence, on-device

Polish rewrites what you just dictated into what you'd have written with time: the point first, rambling cut, false starts and fillers gone, your facts and your casual voice kept. It never adds facts, and if the text is a question or a request, it corrects it rather than answering it.

Hold fn, talk, and tap space while you're still holding it. The pill shows a red “✦ Polish” chip, and when you let go the polished text is typed at your cursor. You can also select text and say an instruction such as “make this more concise”, or open Edit Last Dictation for buttons like Grammar, Concise, Bullets and Email.

• macOS 26 or later. SayWrite itself runs on macOS 15, but Apple's model needs macOS 26.
• A Mac that supports Apple Intelligence, with Apple Intelligence turned on in System Settings › Apple Intelligence & Siri and its model downloaded. Apple lists eligible Macs and languages on its support page.
• AI turned on in SayWrite (SayWrite › AI › Use local AI). It's off by default.

If Apple Intelligence is off, SayWrite tells you and offers a button that opens the right Settings pane. If your Mac isn't eligible, it suggests Ollama or LM Studio instead.

On the developer's M5 Pro Mac, Apple's model answered in about 0.5–1.5 seconds: about half a second (median) for quick fixes like grammar in SayWrite's test suite, and about 1.3 seconds for a full Polish. It needs no loading time, because macOS keeps it ready. Your numbers will vary by Mac.

SayWrite uses Apple's Foundation Models framework, which gives apps the on-device model. The request never leaves your Mac, SayWrite opens no network connection for it, and the text is never logged. Together with on-device transcription, your words stay on your Mac from microphone to cursor. See the security page for the full picture.

They're different things. Apple Dictation turns speech into text. Apple Intelligence includes an on-device language model; macOS uses it for Writing Tools, and apps like SayWrite can use it too. SayWrite combines the two ideas in one gesture: its own on-device transcription, then Apple's model to tidy the result, with prompts written for speech rather than typed text. Comparing dictation apps? See SayWrite vs Apple Dictation.

1. Update to macOS 26 and turn on Apple Intelligence in System Settings.
2. In SayWrite › AI, turn on Use local AI. Set Rewrite engine to Fast to use Apple's model for everything, or leave it on Auto.
3. Type a rambling sentence into the Try It box to see the result and the time it took.
4. Dictate anywhere: hold fn, talk, tap space, let go.

With Match tone to the app (on by default), Polish keeps Slack and Messages replies short with no greeting, writes emails and notes in full sentences, keeps code names exact in Xcode and Terminal, and makes prompts to AI assistants clear and specific. Add a short How I write note, such as “short sentences, British spelling”, stored only on your Mac. Per-app auto-polish can Polish every dictation in apps you choose.

• You want heavier restructuring of long, rambling dictation: a 9B model did more in our tests.
• Apple's safety filter declines a piece of text. SayWrite then inserts nothing and says why.
• The text is too long for the on-device model's context window.
• Your Mac doesn't support Apple Intelligence.

In Auto mode you get both: Polish and emails go to your Ollama or LM Studio model when it's running, and quick fixes use Apple's. Set up your own model.