How do I check if my sentence is grammatically correct?

Paste it into the sentence checker and click once. The AI checks agreement, tense, word order and structure, then returns either a corrected version with a short explanation, or “Correct as written” if there was nothing wrong.

What sentence errors does it catch?

Everything from word-level slips (agreement, tense, articles) to structural problems: run-on sentences, fragments, dangling modifiers, misplaced clauses and ambiguous pronoun references — the errors that make a sentence technically readable but wrong.

Can it check multiple sentences at once?

Yes — paste a short passage (up to 5,000 characters) and each sentence is checked in the context of its neighbors, which matters for tense consistency and references.

Is the sentence checker free?

Yes — free, instant, and no sign-up required.

Free AI Sentence Checker

Is this sentence correct? Paste it and find out in seconds — with fixes for grammar, run-ons, fragments and awkward structure, plus the reason behind each one.

Check & fixStrict formal

0 / 10,000 characters

The result will appear here.

Why use this sentence checker?

Verdict + fix + why

Not just a corrected sentence — a one-line explanation of what was wrong (or confirmation it was right).

Structure-level checks

Run-ons, fragments, dangling modifiers and unclear pronoun references — errors word-level checkers miss.

Minimal edits

The checker keeps your wording wherever possible; it fixes the sentence, it doesn't replace it.

Free and instant

Check sentences one at a time or a short passage at once.

How to use the sentence checker

Paste the sentence
One sentence or a short passage — whatever you're unsure about.
Click “Check Sentence”
Get the corrected version — or confirmation it was already right.
Read the “Why”
A one-line explanation tells you what the issue was, so next time you won't need to check.

About this sentence checker

Sometimes you don't need a whole document checked — you need to know whether this one sentence is right. This free sentence checker answers exactly that question: paste the sentence, and get a corrected version (or confirmation it was already correct) plus a one-line explanation of the issue.

It checks the errors that matter at sentence level: subject-verb agreement, tense, article use, word order — and the structural failures spell checkers can't see, like run-ons, fragments and dangling modifiers (“Walking to work, the rain started” — who was walking?).

The explanation line is what makes it a learning tool rather than a crutch: see the same “Why” twice and you've found a pattern in your writing worth fixing for good. For style improvements beyond correctness, hand the checked sentence to the sentence rewriter.

Frequently asked questions

Sentence checker online
Sentence checker free
Sentence checker AI
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Grammar checker
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Sentence rewriter
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