Word's spelling checker catches most typos automatically

Microsoft Word underlines spelling errors in red as you type. You can fix them by right-clicking the underlined word and selecting the correct spelling from the menu that appears, or by ignoring the suggestion if the word is spelled correctly. Word also has a full spelling and grammar checker you can run on your entire document at once.

The automatic red underline works in Word on Windows, Mac, and the web version. If you don't see red underlines, the spelling checker may be turned off — you can turn it back on in your settings.

Key Takeaways

  • Right-click any red-underlined word to see spelling suggestions and pick the correct one with a single click.
  • You can add words to Word's dictionary so it stops flagging them as errors — useful for proper names and technical terms you use often.
  • The full spelling and grammar checker (Review tab on Windows, or Tools menu on Mac) scans your whole document at once and shows you every error in order.
  • Ignoring a spelling suggestion once does not turn off the checker; Word will flag the same misspelling again in a different part of your document.

Fix spelling errors as you type with right-click

When Word underlines a word in red, right-click it directly. A small menu appears with spelling suggestions at the top. Click the correct spelling to replace the misspelled word instantly.

If the word is spelled correctly — for example, a person's name or a technical term — you have two options. Click Ignore All to stop Word from flagging that word anywhere in the document, or click Add to Dictionary to tell Word the word is correct and should never be flagged again in any document you write.

Run the full spelling and grammar checker on your whole document

To check your entire document at once instead of fixing errors one by one, open the Review tab (on Windows) or the Tools menu (on Mac), then click Spelling & Grammar or Editor. Word scans the document and shows you every spelling error, one at a time, in a panel on the right side of the screen.

For each error, you can click the suggested correction to accept it, click Ignore Once to skip that instance, or click Add to Dictionary to tell Word the word is correct. You can also type your own correction if none of the suggestions are right. Word moves to the next error automatically after you make a choice.

Turn the spelling checker back on if it's off

If you don't see red underlines under misspelled words, the spelling checker is turned off. On Windows, go to File > Options > Proofing, then check the box next to Check spelling as you type. On Mac, go to Word > Preferences > Spelling, then check Check spelling as you type.

In Word on the web, the spelling checker is always on and cannot be turned off. If you're not seeing red underlines there, try refreshing the page or signing out and back in.

Add words to your dictionary so Word stops flagging them

When you add a word to your dictionary, Word treats it as correct everywhere you write. This is useful for proper names, brand names, or technical terms that Word doesn't recognize. Right-click the underlined word and select Add to Dictionary.

Be careful with this option — if you add a misspelled word by mistake, Word will never flag it again. If you need to remove a word from your dictionary later, the process is different on Windows and Mac. On Windows, go to File > Options > Proofing > Custom Dictionaries, then find and edit the dictionary file. On Mac, go to Word > Preferences > Spelling > Custom Dictionaries.

Understand the difference between spelling and grammar checking

The spelling checker only looks for words that are misspelled. The grammar checker looks for sentence structure problems, punctuation errors, and word choice issues — like using "their" instead of "there". When you open the full Editor or Spelling & Grammar tool, it checks both at the same time.

You can turn grammar checking on or off separately from spelling checking. On Windows, go to File > Options > Proofing and look for the grammar options. On Mac, go to Word > Preferences > Spelling. Grammar checking is usually on by default.

Frequently Asked Questions

Why does Word underline a word I know is spelled correctly?

Word's dictionary doesn't include every word in English, especially proper names, brand names, and technical terms. Right-click the word and click Add to Dictionary so Word stops flagging it. You can also click Ignore All if you only want to ignore it in this one document.

Can I undo adding a word to my dictionary?

Yes, but it's more complicated than adding it. On Windows, go to File > Options > Proofing > Custom Dictionaries, find the dictionary file, and edit it to remove the word. On Mac, the process is similar but accessed through Word > Preferences > Spelling.

Does ignoring a spelling error turn off the checker?

No. Clicking Ignore Once skips that one instance of the error, but Word will still flag the same misspelling if it appears elsewhere in your document or in future documents. Only Add to Dictionary makes Word stop flagging a word permanently.

Can I check spelling in Word on my phone?

Word for iPhone and Android has a spelling checker, but it works differently than the desktop version. Misspelled words are underlined in red, and you can tap them to see suggestions. The full spelling and grammar checker tool is not available on mobile.