Limato
Punctuation Checker
Fix commas, periods, apostrophes, and capitalization in one click — without touching your wording or style. Every correction is highlighted. Free, no signup.
How to use the punctuation checker
Paste up to 750 words and click Fix Punctuation. The corrected text appears with every change highlighted, so you can see exactly which comma moved and which capital letter appeared — and learn the rule from it. If a sentence is already punctuated correctly, it comes back untouched. Click Copy and you're done. Your text is processed and returned — never stored.
The checker runs on the same engine as our grammar checker, so if your text also has a spelling slip or a wrong verb tense, it gets fixed along the way.
What it checks
- Commas: comma splices, missing commas after introductory phrases, commas around non-essential clauses, list commas.
- Apostrophes: its vs. it's, your vs. you're, possessives ("the managers' meeting"), contractions.
- Capitalization: sentence starts, proper nouns, days and months, titles.
- End punctuation: run-on sentences that need a period, missing question marks, doubled marks.
- Quotation marks: where periods and commas go relative to closing quotes (inside, in American English).
- Semicolons, colons, hyphens, and dashes: the marks everyone second-guesses.
Comma checker: the mistakes we see most
Commas are most of what a punctuation checker actually fixes, and four errors dominate:
- The comma splice. Two complete sentences glued with a comma: "I sent the report, she never replied." Needs a period, a semicolon, or a connector.
- Missing comma after an introductory phrase. "After the meeting we decided..." reads fine to the writer and slightly off to everyone else: "After the meeting, we decided..."
- Commas around non-essential clauses. "My colleague who sits next to me, agreed" — either both commas or none, depending on what you mean.
- Comma before that. English almost never wants one: "He said, that the deadline moved" loses the comma.
On the Oxford comma the checker is pragmatic: it keeps your list style consistent rather than forcing one convention on you.
Punctuation rules that trip up non-native writers
Punctuation is language-specific, and habits follow you from your first language:
- Comma joins. In Spanish, Russian, or German, a comma can legally join clauses that English separates with a period. That habit produces English comma splices — the single most common error we correct.
- Comma before because and that. Many languages require a comma before subordinate clauses. English usually doesn't.
- Quotation style. « Guillemets », „low quotes", and dialogue dashes all become "straight quotes" in English — with periods and commas placed inside.
- Decimal commas. "2,5%" is correct in most of Europe and wrong in English — it's "2.5%".
- Spacing. No space before ? ! : ; in English — a French habit that survives translation.
These slips are invisible to spell checkers — a punctuation checker is what catches them. For the wording habits that mark text as non-native even when it's technically correct, see 12 ESL patterns native speakers never use.
Correct punctuation is not the same as natural writing
Perfect commas can't save a stiff sentence. "I would like to kindly inform you, however, that the meeting has been rescheduled" is punctuated flawlessly and still sounds like a form letter. If your text is correct but doesn't flow, run it through the paraphrasing tool for a natural restatement, or the AI Humanizer if it reads machine-made. Punctuation fixes the marks; rewriting fixes the rhythm.
Fix punctuation anywhere you write
Limato's Chrome extension corrects and rewrites text inline on any website — Gmail, Slack, LinkedIn, Notion. Highlight, fix, paste back. 20 free rewrites a day.
Add to Chrome — FreeFrequently asked questions
Is the punctuation checker free?
Yes. Checks on this page are free with a daily limit, no signup. The Limato Chrome extension gives 5 free rewrites a day without sign-in, or 20 a day with a free account.
Can it punctuate this sentence for me?
Yes — paste the sentence and click Fix Punctuation. It adds missing commas, periods, apostrophes, and capital letters, and works on anything from a single sentence to a full essay (up to 750 words per check).
Is this also a comma checker?
Yes. Commas are the largest share of what it fixes: comma splices, missing commas after introductory phrases, commas around non-essential clauses, and extra commas English doesn't want.
Will it change my words?
No. It fixes punctuation, capitalization, and any grammar or spelling errors it finds, but keeps your wording and sentence structure. If you want the text rephrased, use the paraphrasing tool instead.
Does it work for languages other than English?
It works best for English. Spanish speakers checking Spanish text should use our corrector gramatical, which applies Spanish punctuation rules.
Is my text stored?
No. Text is sent to the rewrite API, processed, and returned — not stored, logged, or used to train models.