About

This site exists for one job — a punctuation checker that gives a clear answer quickly and shows how it was reached.

How we test the calculations

Before an update is published, the tool runs through 126 automated checks in a real browser: worked examples are recalculated, edge cases and wrong input are tried, and the layout is checked on desktop and on a phone.

Sources

The formulas and reference values in the guides follow published standards and primary sources, linked where they are used: owl.purdue.edu, chicagomanualofstyle.org.

Editorial principles

The editorial team writes for one reader: someone who needs a reliable answer now. That means worked examples, units spelled out, honest limits and no sponsored recommendations.

Keeping it current

Published October 8, 2026, last reviewed October 12, 2026. Corrections are welcome via the contact page; confirmed fixes go out with the next update.

How the site is paid for

Advertising keeps the site free. Ads are kept separate from results and do not influence what the tool shows.

— Punctuation Checker editorial team