Free Punctuation Checker
Find common punctuation problems as you type, review each suggestion, and apply clear corrections with one click.
Checks common punctuation patterns in your browser.
Free from the team behind Typeahead. The autocomplete for your whole Mac.
Get TypeaheadWhat is a punctuation checker?
A punctuation checker reviews the marks that organize a sentence, including commas, periods, colons, semicolons, question marks, exclamation points, and brackets. It highlights patterns that may interrupt clarity and suggests a mechanical correction when one is clear. Punctuation can depend on meaning, so the writer still makes the final choice.
Why It Matters
Small marks shape the whole sentence.
Punctuation separates ideas, signals pauses, closes thoughts, and shows how parts of a sentence relate. This checker focuses on common, explainable patterns instead of silently rewriting your draft.
Source: Purdue OWL, Punctuation
Where it matters
Emails, essays, reports, applications, project updates, articles, and any draft where a misplaced mark could slow the reader down.
Checks punctuation spacing, repeated marks, sentence endings, list structure, clause boundaries, introductory commas, and paired brackets as you type. Every suggested change stays under your control.
How It Works
Check punctuation as you write.
Add your text
Paste a draft or keep writing directly in the editor.
Review the underlines
Open each marked passage to see the pattern and suggested change.
Choose each correction
Apply a clear fix, dismiss a suggestion, or edit the punctuation yourself.
See It Work
Nine fixes in five sentences.
What you paste
However ,this works. The agenda has three parts research , writing and editing. Because the team was ready we started early. She finished the draft and he reviewed it. The draft is short the review is thorough
However, this works. The agenda has three parts: research, writing, and editing. Because the team was ready, we started early. She finished the draft, and he reviewed it. The draft is short; the review is thorough.
This is the checker's actual output for that text: two spacing fixes around “However”, a list colon, a stray space, a serial comma, an introductory comma, a clause comma, a semicolon, and a final period.
When do you need a comma?
Three situations cover most missing commas, and the checker looks for all three. First, after an introductory word or clause: “Although the draft is short, the review is thorough.” Second, before and, but, or so when it joins two complete sentences: “She finished the draft, and he reviewed it.” Third, before the last item in a list you introduced formally. You do not need one when two verbs share a subject, as in “She finished the draft and reviewed it”, and the checker will not suggest one there.
What It Catches
Six kinds of punctuation problem.
Each rule is narrow on purpose. It fires when the pattern is clear and stays quiet when the sentence could be read two ways.
Introductory commas
“Because the team was ready we started early” gets a comma after “ready”. So do openers like “However” and “Finally”.
Commas between clauses
“She finished the draft and he reviewed it” joins two complete sentences, so a comma goes before “and”.
Run-together sentences
“The draft is short the review is thorough” has no boundary. The checker suggests a semicolon after “short”.
Colons before lists
“Three parts research, writing, and editing” needs a colon after “parts”. Sentences that merely mention parts are left alone.
Sentence endings
A line with no final mark gets a period, or a question mark when it clearly asks something.
Spacing and brackets
Removes a space before a comma, adds a missing one after, collapses “!!” to one mark, and flags a bracket with no partner.
Before the Final Check
Keep the thought moving.
A checker tidies the marks once a sentence exists. Typeahead is a Mac app that helps it exist: grey suggestions for the next few words appear inline while you type in Mail, Slack, or Google Docs.
Draft first, punctuate second. Press Tab to take a suggestion or type past it. Everything runs on your Mac, for $79 once.
Get TypeaheadPunctuation Checker
Common questions.
A punctuation checker reviews marks such as commas, periods, colons, semicolons, question marks, exclamation points, and brackets. It identifies patterns that may need attention and lets you decide which corrections fit your sentence.
Paste or type your text in the editor. Common punctuation issues appear with a wavy underline. Open a suggestion to read the explanation, apply the correction, or dismiss it.
Yes. Most of what it finds is commas. It suggests one after an introductory word such as 'However' or 'Finally', after an opening clause that starts with because, although, when, or if, before a conjunction that joins two complete sentences, and before the last item of a formally introduced list.
When 'and' joins two complete sentences, each with its own subject and verb: 'She finished the draft, and he reviewed it.' When the second half shares the subject, no comma is needed: 'She finished the draft and reviewed it.' The checker flags the first case and leaves the second alone.
No. An ordinary list like 'red, white and blue' is left as you wrote it, because both styles are accepted. It suggests the serial comma only in a formal list introduced with a count and a colon, such as 'three parts: research, writing, and editing'.
When two complete thoughts sit side by side with nothing between them, as in 'The draft is short the review is thorough', it suggests a semicolon at the boundary. A period or a conjunction can work just as well, so edit the suggestion if you prefer one.
No. It does not judge apostrophes, quotation marks, hyphens, or dashes, because the right choice there depends on meaning. For paired marks it checks parentheses, square brackets, and curly braces only.
Web addresses, email addresses, decimals and version numbers like 3.5 or 2.0.1, initialisms like U.S., the abbreviations e.g. and i.e., and an ellipsis of three or more periods. None of these are treated as spacing or repeated-mark errors.
No. This tool is punctuation only. Our Grammar Checker runs these same punctuation rules together with US English spelling and a set of grammar and sentence-structure checks, so use that one for a full pass.
Yes to both. There is no account or sign-up, and every rule runs as JavaScript in your browser. The text you check is never uploaded, so we could not store it if we wanted to.
Finish the thought, then polish the marks.
Typeahead suggests the rest of your sentence in every Mac app. Bring the draft back here when it is time for commas.
Get Typeahead — $79Mac only. One-time purchase. Runs offline.