Punctuation mistakes it finds
Grammar engines focus on words. This checker focuses on the marks between them, using deterministic rules that are fast and predictable:
- Spacing: double spaces between words, a space before a comma or full stop, a missing space after a comma or between sentences (“end.Next”), spaces just inside parentheses.
- Unmatched marks: an opening bracket, parenthesis or curly quote that’s never closed in the paragraph, a stray closing one, or an odd number of straight double quotes.
- Repeated marks: “,,”, “;;”, two full stops, and emphatic “!!” or “??”.
- Dashes: a spaced hyphen (“word - word”) used where a dash belongs.
- Apostrophes: “1990’s” for the decade (it should be “1990s”) and the impossible “its’”.
- Capitalisation after a full stop and missing end punctuation on long paragraphs.
Most issues come with a one-click fix.
Style choices it leaves to you
Whether to use the serial (Oxford) comma, single or double quotes, and spaced or closed dashes are house-style decisions, not errors. The Consistency Checker reports when a text mixes them, and the Typography Fixer converts to proper dashes and curly quotes.
Worked example
Here is what the Punctuation Checker returns for its built-in example. Click Try an example in the tool above to load it, then change it as you like.
Hello ,world.This is( odd ) punctuation!! The 1990's were great - weren't they? "Quote without an end. Its' wrong..| Found | Type | Suggestion |
|---|---|---|
| “.” | Spacing | . |
| “( ” | Spacing | ( |
| “ )” | Spacing | ) |
| “!!” | Style | ! |
| “1990's” | Apostrophe | 1990s |
| “ - ” | Dash | —, – |
| “"” | Unmatched mark | — |
| “Its'” | Apostrophe | its, it’s |
Questions
Does it check comma placement?
It checks mechanical comma errors such as spacing and doubled commas. Grammar-based comma rules (like comma splices) are better handled by the Grammar Checker.
Is “1990’s” wrong?
For the plural decade, yes: write “1990s”. An apostrophe is only correct for possession (“1990’s best film”) or for a dropped century (“the ’90s”).
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