How-to

How to spell check on iPhone: every built-in tool, and when to use each

Published 3 October 2026 · 6 min read

There is no single spell-check button on iPhone. There are four separate tools that check spelling, each switched on in a different place and each good at a different moment. Knowing which one you are looking at makes all of them easier to live with.

1. Auto-Correction: fixes as you type

This is what “spell check” usually means on a phone. Apple describes Auto-Correction as using your keyboard dictionary to spellcheck words as you type, correcting misspelled words automatically. It is on by default, and it acts the moment you press space or a punctuation key.

Since iOS 17, a word it has just corrected is briefly underlined so you can see what changed. To get your own spelling back, tap the underlined word, then tap your spelling: Apple lists it first.

Good for: quick messages, where a typo fixed without asking is a typo you never see. Watch out for: words it does not know. Names, jargon and words from another language can look like typos to it, which is the subject of why iPhone autocorrect changes words you typed correctly.

2. Check Spelling and Grammar: underlines, never changes

On iOS 27, Settings › General › Keyboard has a switch Apple calls Check Spelling and Grammar, next to Auto-Capitalization and Auto-Correction. With it on, a word it doubts is underlined in red. Tap the word to see suggested corrections, then tap one to replace it, or simply type the correction yourself. Nothing changes until you choose.

This is the switch to know about if you dislike autocorrect. Turn Auto-Correction off and leave Check Spelling and Grammar on, and your typos stay visible but nothing is rewritten behind your back. How to turn off autocorrect on iPhone walks through that set-up and the other in-between options.

Good for: longer writing, where you want to decide. Watch out for: it marks problems; it does not fix them for you, so a red line you scroll past stays a typo.

3. Proofread with Writing Tools

On an iPhone with Apple Intelligence, select the text you want to check, tap the Writing Tools button, then tap Proofread. Apple says Writing Tools are available in most places you write, including third-party apps and websites.

There are conditions. Apple lists Apple Intelligence on iOS 27 for an iPhone 15 Pro, iPhone 15 Pro Max, or an iPhone 16 model or later, and says it is not available in all languages or regions. The Feature Availability page lists which languages Writing Tools support.

Good for: an important email before you send it, checked in one go. Watch out for: it works on text you have already written and selected, not while you type, and not on older phones.

4. Check Spelling in Pages, Numbers and Keynote

Apple’s own document apps have a spelling check that works even with Auto-Correction off. In a Pages document, open the app’s settings from the toolbar, tap Auto-Correction, and turn on Check Spelling. Misspelled and unrecognized words are underlined in red; tap one, then tap the correct spelling. Numbers and Keynote work the same way.

Two details from Apple’s Pages guide are worth knowing:

• You can teach it a word. Tap the underlined word, then Learn Spelling. Apple says the word is added to the dictionary used by Pages and other apps. Unlearn Spelling takes it out again.
• It checks the keyboard’s language, not the document’s. Apple notes that spelling is checked according to the language of the keyboard you are using. Write in one language with another keyboard active, and correct words will be flagged.

Why spell check flags words that are right

When the red lines or the corrections are wrong, the cause is usually one of three things.

It has never seen the word

Every checker works from a word list. A surname, a product name or a new piece of slang is not on it, so it looks like a typo. Teach it with Learn Spelling where that is offered, and to stop Auto-Correction replacing a word, add it as a Text Replacement with an empty shortcut, as Apple suggests (Settings › General › Keyboard › Text Replacement).

It is checking the wrong language

Because the keyboard’s language decides what counts as correct, a second language you write in reads as a string of errors. Adding a keyboard for it helps, and for some pairs Apple offers a bilingual keyboard that follows you between two languages. How to type in two languages on iPhone covers the steps and what to do when your pair is not supported.

It learned something it should not have

Keyboards learn from what you type, and that includes the occasional mistake. Apple’s way to clear it is Settings › General › Transfer or Reset iPhone › Reset › Reset Keyboard Dictionary, which erases every word you have added at once, the good with the bad.

What a spell-check keyboard adds

All four tools above come with iOS and cost nothing. Pilcrow, the keyboard we make, is for people who want the checking to happen while they type, without the rewrites. It is listed on the App Store as a spell-check keyboard because that is its main job.

• It corrects, and it leaves real words alone. On held-out text, Pilcrow changes a correctly spelled word fewer than 7 times in 1,000, and restores 61–72 % of words typed with a genuine slip. Both figures are quoted at the worst end of the range across the languages it ships.
• Every language you enable counts. Turn on the languages you write and it tells them apart word by word, so the wrong-keyboard problem above does not arise. It types in forty languages.
• A whole message, checked at once. The ✨ button in the suggestion bar re-reads everything you have typed, repairs the slips, and tells you how many words it changed; one more tap puts them all back. It fixes spelling, not grammar or style, and it runs on the phone itself.
• Check one language, correct another. With several languages enabled, you can switch corrections off for one of them. That language stays spell-checked, with suggestions in the bar, but is never auto-corrected.
• Your own spelling stays one tap away. When it corrects, the word you actually typed sits first in the suggestion bar. Undo a correction once and it is never applied to that word again.
• Missing accents come back. Type a word without its accents and Pilcrow restores them 74–85 % of the time, in languages that use them.

Which one to use when

• Texting: Auto-Correction on, or a keyboard that corrects without rewriting real words.
• Writing you will reread: Check Spelling and Grammar on, so doubts are marked rather than changed.
• One important message: Writing Tools › Proofread, where your iPhone and language support it, or Pilcrow’s ✨ button for spelling.
• A document: Check Spelling inside Pages, Numbers or Keynote, and Learn Spelling for the names it keeps flagging.

Last checked October 2026 against Apple’s iPhone User Guide for iOS 27 and the Pages User Guide for iPhone. Apple, iPhone, Pages, Numbers, Keynote and Apple Intelligence are trademarks of Apple Inc.; Pilcrow is not affiliated with Apple. If anything here is out of date, write to info@pilcrowtype.com.

Sources

1. Apple, How to use Auto-Correction and predictive text on your iPhone (what Auto-Correction does; underlined corrections since iOS 17)
2. Apple, Select, edit, and move text on iPhone (Check Spelling and Grammar; red underlines; undoing an autocorrection)
3. Apple, Use Writing Tools to write, improve, and summarize content on iPhone (Proofread; device requirements)
4. Apple, iOS and iPadOS 27 Feature Availability (Writing Tools languages)
5. Apple, Check spelling in Pages on iPhone (Check Spelling; Learn Spelling; keyboard language)
6. Apple, Set up shorthand for frequently used text on iPhone (Text Replacement)
7. Apple, Reset iPhone settings to their defaults (Reset Keyboard Dictionary)