How to Spell Check on a Mac (and Check Grammar Too)

Does a Mac have spell check?

Yes. macOS has a spelling and grammar checker built in, and Mail, Notes, TextEdit, and many other apps use it. It works quietly as you type, and the marks it leaves tell you what it found:

• Red underline: a misspelled word. It stays underlined until you fix it, ignore it, or teach your Mac the word.
• Dotted blue underline: a possible grammar problem. You only see these once grammar checking is on. Move the pointer over one to see what’s wrong.
• A brief solid underline: a word that autocorrect just changed for you. That’s autocorrect, not spell check, and it has its own settings.

The checker flags problems; it doesn’t rewrite anything unless you pick a suggestion. If words are changing on their own, that’s autocorrect, and our guide on how to turn off autocorrect on a Mac explains how to tame it. Apple’s own guide to typing suggestions and correcting mistakes covers the same settings.

How to spell check a whole document on a Mac

Red underlines are easy to miss in a long email or report. To walk through every mistake in order:

1. Click anywhere in the document, email, or note you want to check.
2. Choose Edit › Spelling and Grammar › Check Document Now. Your Mac highlights the first mistake it finds.
3. Press ⌘; (Command-Semicolon) to jump to the next misspelled word.
4. Control-click a highlighted word to see suggested spellings, and choose one to replace it.

Tip: Apple notes that keyboard shortcuts can vary by app. If ⌘; does nothing where you’re typing, use the Edit menu instead.

Use the Spelling and Grammar window for long documents

Choose Edit › Spelling and Grammar › Show Spelling and Grammar, or press ⇧⌘: (Shift-Command-Colon). The window shows each mistake with its suggestions, and Apple says it’s easier to use with long documents than Control-clicking word by word. Both shortcuts are on Apple’s list of Mac keyboard shortcuts.

How to turn on grammar check on a Mac

Grammar checking has a switch of its own. To turn it on in an app:

1. Open the app you’re writing in, such as Mail, Notes, or TextEdit.
2. Choose Edit › Spelling and Grammar.
3. Choose Check Grammar With Spelling. A checkmark next to it means it’s on.

Grammar problems now get a dotted blue underline, and you can hover over one to see a short description of the issue. Treat it as a safety net rather than an editor: it points out problems, but it won’t restructure a clumsy sentence for you.

Make sure spelling is checked as you type

In most apps, the same menu has Check Spelling While Typing. If it has no checkmark, you won’t see any red underlines until you run Check Document Now. Mail does it slightly differently: choose Edit › Spelling and Grammar › Check Spelling, then While Typing, Before Sending, or Never.

How to add a word to the dictionary on a Mac

Names, brands, and jargon get a red underline because they aren’t in your Mac’s dictionary. Control-click the word and pick the option that fits:

Remove a word you added by mistake

It’s easy to click Learn Spelling instead of a suggestion, and then a typo counts as correct forever. To take it back:

1. Type the word exactly as you taught it, in an app that uses the Mac’s checker, such as TextEdit or Notes.
2. Control-click the word.
3. Choose Unlearn Spelling. From now on it’s flagged like any other misspelling.

Note: You may find advice online to edit a hidden word-list file by hand instead. Unlearn Spelling is simpler and safer, so start there.

How to change the spell check language on a Mac

By default, the Mac picks the spelling language from what you type (the setting is called Automatic by Language). To choose a language yourself, or check several at once:

1. Choose Apple menu › System Settings, then click Keyboard in the sidebar. You may need to scroll down.
2. Under Text Input, click Edit.
3. Click the Spelling pop-up menu and choose a language. To check more than one, choose Set Up, select each language you write in, and click Done.
4. Click Done to close the panel.

Tip: If you write in two languages, leave it on Automatic by Language or choose both in Set Up. If you pick just one, words in the other language get red underlines.

Apps with their own spell check settings

Some apps add their own checker or their own switches, so the Edit menu settings above don’t cover them. If an app’s Edit menu has no spelling commands at all, look in its settings instead.

Note: Chrome’s Enhanced spell check is worth a second look if you type anything confidential into web apps. Google’s help page explains the difference between the two modes.

New in macOS 27: Apple Intelligence proofreads as you type

macOS 27 Golden Gate, released on September 14, 2026, adds automatic proofreading. In Apple’s words, Apple Intelligence now “automatically proofreads for users as they type across the system”, including in most third-party apps. MacStories describes blue underlines under spelling and grammar mistakes that can take a few seconds to appear.

• You need Apple Intelligence: a Mac with M1 or later (or the MacBook Neo), with Apple Intelligence on and a supported language.
• Intel Macs don’t get it. macOS 27 runs only on Apple silicon; macOS Tahoe 26 is the last version for Intel Macs.
• The classic checker is still there. Red underlines, Check Document Now, and Learn Spelling work as before on macOS 27.

Apple’s help pages don’t yet say how to switch the new proofreading off on its own, or exactly which languages it covers, so expect details to shift with updates. On any Mac with Apple Intelligence, you can also select text and use Writing Tools › Proofread to check a whole passage on demand. Our guide to Apple Intelligence Writing Tools on Mac covers both, step by step.

Spell check not working on your Mac? Try these fixes

Work down this list. Most problems are a switched-off menu item or the wrong language.

1. Check the Edit menu. In the app you’re using, open Edit › Spelling and Grammar and make sure Check Spelling While Typing has a checkmark. In Mail, choose Check Spelling › While Typing.
2. Check the language. If almost every word is underlined, or none are, the wrong spelling language may be selected. Look at the Spelling pop-up under System Settings › Keyboard › Text Input › Edit.
3. Check for the app’s own checker. Word, Chrome, and Slack have their own spelling settings (see the table above).
4. Look for a word you taught by mistake. If one particular typo is never flagged, it’s probably in your dictionary. Type it, Control-click it, and choose Unlearn Spelling.
5. Quit and reopen the app. If a setting you changed doesn’t seem to apply, reopen the app, and restart your Mac if it still doesn’t.
6. Make sure it’s really spell check. If words are being changed rather than underlined, that’s autocorrect, which has separate settings.

When the built-in checker isn’t enough

The Mac’s checker tells you what’s wrong, but you still fix each mistake by hand. If that gets tedious, you have a few options:

• Writing Tools (Apple Intelligence, M1 or later): select text and choose Proofread to have the whole passage corrected, with an explanation for each change. It comes with your Mac.
• An always-on checker such as Grammarly or LanguageTool underlines as you type and works across devices. We compare the options in Grammarly alternatives for Mac.
• A fixer that works on your selection, like MacWriteBuddy, below.

In MacWriteBuddy: Select text in any app and press ⌃⌥G. MacWriteBuddy corrects the spelling, grammar, and punctuation right where you typed it, and shows a preview of every change before anything is replaced. It’s free, needs no account, and runs on macOS 14 or later, Intel Macs included, with a model that runs on your Mac, your own AI provider key, or Apple Intelligence (macOS 26 or later, on a Mac that supports it). It doesn’t underline as you type; it works when you ask. See how one-shortcut fixing works.

Weighing up a dedicated tool? Our guide on how to choose a grammar checker for your Mac walks through what matters: every-app support, privacy, offline use, and price.