How to Add Words to Your Personal Dictionary on Mac

There are three ways to add words to your personal dictionary on Mac. The fastest is to right-click a red-underlined word and choose "Learn Spelling." You can also add words directly in System Settings under Keyboard, or create a Text Replacement rule that maps an abbreviation or misspelling to your intended word. All three methods update the shared macOS dictionary instantly.

Method 1: Right-click and choose Learn Spelling

This is the quickest method and works without opening any settings panel. It is most useful when you are already typing and notice that macOS is flagging a word you use regularly.

How to do it: Find a word with a red squiggle underneath it in any supported app - Mail, Notes, Pages, Safari, TextEdit, and most native Mac apps will show these. Right-click the word (or Control-click if you are using a single-button mouse or trackpad). In the context menu that appears, select "Learn Spelling."

The word is added to your macOS personal dictionary immediately. The red underline disappears, and the word will no longer be flagged as a misspelling in any app that uses the macOS spell-checking system. The change takes effect in all supported apps without restarting them.

According to Apple's developer documentation, the personal dictionary is shared across all apps that use the NSSpellChecker API - so adding a word once protects it everywhere that API is active.

Method 2: Add words via System Settings

If you want to add multiple words at once, or if the word you want to add is not currently flagged anywhere on screen, the System Settings approach is more practical.

How to do it:

• Open System Settings (the gear icon in your Dock or from the Apple menu)
• Click Keyboard in the left sidebar
• Click the Edit button next to Input Sources
• Scroll down to find the User Dictionary section
• Click the + button at the bottom of the word list
• Type the word exactly as you want it recognised, then press Return

The word is saved to your dictionary and will be treated as valid in all NSSpellChecker-compatible apps going forward. You can add as many words as you need in one session - the list is not limited in size.

To remove a word you added accidentally, select it in the User Dictionary list and click the - button or press the Delete key. The word will revert to being flagged in supported apps.

Method 3: Create a Text Replacement rule

Text Replacements are slightly different in purpose - they are primarily for adding custom autocorrect rules rather than simply teaching macOS to accept a word. But they are very useful for managing both abbreviations and recurring misspellings.

How to do it:

• Open System Settings and click Keyboard
• Click the Edit button next to Input Sources
• Look for the Text Replacements section at the top
• Click the + button to add a new rule
• In the Replace field, type the abbreviation or misspelling you want to trigger the replacement
• In the With field, type the correct expanded text
• Press Return to save

For example, if you regularly type "btw" and want it expanded to "by the way," the Replace field gets "btw" and the With field gets "by the way." If you want to stop macOS correcting "dont" to "don't," put "dont" in both fields - this forces macOS to return the word unchanged instead of substituting.

Text Replacements sync across your Apple devices via iCloud, which means a rule you add on your Mac will also apply on your iPhone and iPad. This is the most powerful of the three methods for managing custom vocabulary consistently.

Where is the Mac personal dictionary stored?

The macOS personal dictionary lives in ~/Library/Spelling/. The primary file is a plain text file named after your language - for most English-language Macs it is called LocalDictionary. Each word you add via the right-click or System Settings methods is written to this file on a new line.

You can open and edit this file directly in a text editor if you need to bulk-add or remove terms - though using the System Settings interface is safer and ensures the changes are picked up immediately by running apps. If you edit the file while any apps are open, you may need to restart them for the changes to take effect.

Why the macOS dictionary does not affect every app

The personal dictionary is powerful, but it has a significant limitation: it only applies to apps that use the NSSpellChecker API. Apple's own apps - Notes, Mail, Pages, Safari, TextEdit - all use this API and will respect your dictionary. But a large number of popular third-party apps do not.

Slack's desktop app, VS Code, Notion, and essentially all Electron-based apps bypass NSSpellChecker entirely. From macOS's perspective, these apps never ask whether a word is valid - so your personal dictionary entries are simply never consulted. Studies of typical Mac workflows find that knowledge workers spend over 60% of their typing time in apps that fall into this category.

If you regularly type technical terms, names, or domain-specific vocabulary in apps like Slack or VS Code, the macOS personal dictionary will not help you there. See how to fix autocorrect on Mac for a full breakdown of how to handle this gap.

How Charm handles custom vocabulary differently

Charm uses a different correction mechanism from the macOS personal dictionary system. Rather than relying on NSSpellChecker, Charm uses the macOS Accessibility API to monitor and correct text across every app - including Slack, VS Code, and every other app where the built-in dictionary has no effect.

This means the two systems operate independently. Adding a word to your macOS User Dictionary does not affect how Charm behaves, and Charm's settings do not write to ~/Library/Spelling/.

If Charm corrects a word you want to keep, pressing Cmd+Z or Backspace immediately after the correction will undo it. You can also configure exceptions directly in Charm's settings. For more on how Charm compares to the built-in macOS system, see Charm vs macOS Autocorrect.

Frequently asked questions

How do I add a word to my Mac dictionary without right-clicking?

Open System Settings, click Keyboard, then click Edit next to your input source. Scroll to the User Dictionary section and click the + button to type a word directly. This adds the word to the shared macOS personal dictionary and works identically to the right-click Learn Spelling method.

Where is the Mac personal dictionary stored?

The macOS personal dictionary is stored in ~/Library/Spelling/. The main file is a plain text file - typically named LocalDictionary for English. You can edit it directly in a text editor, though using System Settings or right-click is safer and takes effect immediately without restarting apps.

Does adding a word to the Mac dictionary work in every app?

Only in apps that use the macOS NSSpellChecker API - primarily Apple's own apps like Notes, Mail, Pages, and Safari. Third-party apps including Slack desktop, VS Code, and Electron-based apps do not use NSSpellChecker, so they will not benefit from personal dictionary entries.

Can I remove a word I accidentally added to my Mac dictionary?

Yes. Open System Settings, go to Keyboard, click Edit next to your input source, and find the User Dictionary section. Select the word you want to remove and press the Delete key, or click the - button. The word will be treated as a potential spelling error again in supported apps.

How do I stop Charm from correcting a word I want to keep?

Press Cmd+Z or Backspace immediately after Charm corrects a word to undo the correction. You can also add exceptions in Charm's own settings. Note that Charm uses a separate correction mechanism from the macOS personal dictionary, so System Settings entries do not affect Charm's behaviour.