Free sentence checker
Paste a sentence to find grammar, spelling and punctuation mistakes and fix each one in one click. It does not judge sentence structure: for run-ons and fragments, use the test below. No sign-up.
Paste your text and click “Check grammar”. Each issue is underlined by category: grammar, spelling, punctuation or style.
- Grammar
- Spelling
- Punctuation
- Style
Free to use. Your text is checked and not stored.
- No sign-up required
- Free up to 10,000 characters
- 14 languages, 6 English variants
- Free, no sign-up
- One-click corrections
- Grammar, spelling and punctuation
Six sentence errors and how to fix them
The checker flags agreement, verb-form and capital-letter errors for you. Run-ons, comma splices and fragments usually need your own eye, so learn to spot them.
Run-on sentence
Two complete sentences joined with nothing between them. Split them, or join them with a comma and a word like and, but or so.
Incorrect:
I was tired I went to bed.Correct: I was tired, so I went to bed.Comma splice
Two complete sentences joined by a comma alone. Use a full stop, a semicolon, or add a joining word after the comma.
Incorrect:
It rained all day, we stayed in.Correct: It rained all day; we stayed in.Sentence fragment
A group of words punctuated as a sentence but missing a subject, a verb or a complete thought. Attach it to the sentence it belongs to.
Incorrect:
Because the train was late.Correct: We missed the start because the train was late.Subject-verb agreement
A singular subject takes a singular verb, however many words sit between them.
Incorrect:
The list of items are on the desk.Correct: The list of items is on the desk.Wrong verb form
After have, has or had, use the past participle. After did or does, use the base form.
Incorrect:
She has went home.Correct: She has gone home.Capital letter and end mark
A sentence starts with a capital letter and ends with a full stop, a question mark or an exclamation mark.
Incorrect:
where did they goCorrect: Where did they go?
Is this a complete sentence?
A rule-based checker rarely flags a run-on or a fragment, because every word in it can be correct. This test finds them.
It has a subject
Someone or something the sentence is about. In “The dog barked”, the subject is the dog. In a command such as “Sit down”, the subject is an understood “you”.
It has a verb
A word that says what the subject does or is, in a form that shows time: barked, is barking, will bark. “Barking” alone is not enough.
It finishes a thought
It can stand on its own. A clause that starts with because, although, when or if needs a second half to complete it.
How to check a sentence in 3 steps
Paste or type your sentence
One sentence or a whole paragraph, up to 10,000 characters. Pick your language or English variant.
Click “Check grammar”
Each problem is underlined by type: grammar, spelling, punctuation or style, with a short explanation.
Correct it in one click
Click a suggestion to apply it, or ignore it. Then reread the sentence with the three-part test above.
Checking more than a sentence?
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Sentence checker questions
Check your sentence
Free, no sign-up, one-click corrections for up to 10,000 characters.