Setting up Charm takes a few minutes. You download the app, drag it to Applications, and a short setup guide walks you through your licence key, two macOS permissions and the choice of AI engine. After that Charm lives in your menu bar and corrects as you type, with no account and no subscription.

Step 1: Buy and download Charm

Go to www.theodorehq.com/charm and click Buy Now. Charm is a one-time $19.99 purchase. Your licence key arrives by email; it starts with CHARM-. Download the Charm .dmg from the site. The app is around 18 MB.

What you need: an Apple Silicon Mac (M1 or later) on macOS 14 Sonoma or later. Charm's on-device AI uses Apple's chip, so it does not run on Intel Macs.

Step 2: Install Charm

Open the .dmg and drag Charm into the Applications folder, then open it from Applications or Spotlight. The setup guide opens straight away.

Step 3: Follow the setup guide

The guide has six short screens. This is what each one asks for:

  1. License. Paste the key from your purchase email. Charm checks it once and remembers it; the key works on up to 3 Macs.
  2. Permissions. Charm needs two: Accessibility, so it can read and correct the text you are writing, and Input Monitoring, so it knows when you type. Each row has a button that opens the right page in System Settings. They sit in two separate lists, so check both are switched on.
  3. Turn off macOS autocorrect. The built-in autocorrect and Charm can fight over the same word. The guide shows where to switch it off: System Settings > Keyboard, click Edit next to Input Sources, and turn off "Correct spelling automatically".
  4. Choose your engine. Pick Fast (about 1.5 GB, runs on Macs with 8 GB of memory), Best Quality (about 2.3 GB, wants 16 GB), or Built-In Spellcheck, which needs no download but leaves out grammar fixes and next-word suggestions. Charm only offers the models your Mac can run, and you can change your mind later in Settings > General.
  5. Modes. Charm corrects as you type. Code editors start in Manual, where you select text and press Option-Command-V, so your code is never changed while you type.
  6. Try it out. Start using Charm, or take the two-minute interactive guide first.
Privacy note: the permissions let Charm see the text you are writing; they do not send it anywhere. Every correction and prediction runs on your Mac, and Charm works offline.

Step 4: Turn on the features you want

Click the Charm icon in the menu bar to switch each feature on or off:

Spells - spelling correction

On from the start. Spells fixes misspellings as you finish each word, with a brief glow and no red underlines. For how it behaves day to day, see How to Use Charm's Spells Feature.

Polish - grammar correction

Off until you switch it on. Polish checks each sentence when you finish it and fixes mistakes such as "she don't" or a missing capital. It uses the AI engine you picked, so it is not available with Built-In Spellcheck.

Oracle - word prediction

Off until you switch it on. Oracle finishes the word you are typing in light grey text; press Tab to accept it or keep typing to ignore it. When you pause after a space, it also suggests your next few words, using the AI engine. See How to Use Oracle Word Prediction in Charm.

Step 5: Check it is working

Open Notes or TextEdit and type "teh" followed by a space. It should become "the". If Polish is on, type "she don't know the answer." and the sentence should be fixed when you type the full stop. If nothing changes, open System Settings > Privacy & Security and check that Charm is switched on under both Accessibility and Input Monitoring, then quit and reopen Charm so macOS picks up the change.

Optional: Start at login and per-app settings

To have Charm open whenever you log in, turn on Start at Login in Settings > General. To change how Charm behaves in one app or website, open Settings > Customise: you can set any app to Auto or Manual, or switch Spells, Polish and Oracle off for it on their own.

Frequently asked questions

Does Charm require an account or subscription?

No. Charm is a one-time $19.99 purchase with no account and no subscription. You buy it once and own it. A single licence covers up to 3 Macs and includes all future updates.

Why does Charm need two permissions?

Accessibility lets Charm read and correct the text you are writing, and Input Monitoring lets it notice when you type. Without both, it cannot correct anything. You grant them once in System Settings > Privacy & Security, and the setup guide opens the right pages for you.

Does Charm send my text to the cloud?

No. All correction happens 100% on-device. Your keystrokes never leave your Mac. Charm does not require an internet connection after installation, making it safe for confidential and sensitive content.

What is the difference between Spells, Polish, and Oracle?

Spells corrects spelling as you type. Polish fixes grammar when you finish a sentence. Oracle finishes words and suggests the next few, and you press Tab to accept. Each can be switched on or off from the menu bar.

Can I stop Charm from correcting text in specific apps?

Yes. Open Settings > Customise and find the app under Apps, or the site under Websites. You can switch Spells, Polish and Oracle off for it, or set it to Manual so Charm only corrects when you press Option-Command-V.