Skip to content

Commonly Confused Words Checker

Paste your text to highlight commonly confused words — their/there/they're, affect/effect, its/it's, then/than — with the usage rule for each pair. The tool flags candidates for you to verify; it does not know which word you meant, so review each highlight against its rule.

Frequently Asked Questions

What does the confused words checker do?
It scans your text against a list of about 45 commonly confused word pairs and triples — their/there/they're, affect/effect, its/it's, then/than — highlights every occurrence, and shows the usage rule for each pair so you can verify you used the right one.
Does the tool know which word I meant to use?
No. The tool flags candidates for you to verify — it cannot tell from context which word you intended. Each highlight comes with the rule for its pair so you can decide quickly whether your usage is correct.
Which confused word pairs are covered?
Around 45 pairs and triples, including their/there/they're, its/it's, affect/effect, then/than, your/you're, to/too/two, loose/lose, whose/who's, accept/except, advice/advise, complement/compliment, principal/principle, stationary/stationery, weather/whether, and cite/site/sight.
Why are correct words highlighted too?
Every member of a confused pair is highlighted, correct or not, because the tool cannot judge intent. Most highlights will be fine — the value is in the few that are not, which spell checkers miss because the wrong word is still a real word.
Is my text sent to a server?
No. The check runs entirely in your browser — your text is never uploaded, stored, or shared.

Related Tools