The Chicago Manual of Style Online is the digital edition of The Chicago Manual of Style, a long-established reference for style, usage, and grammar. Published by the University of Chicago, it provides practical, authoritative guidance for writers, editors, proofreaders, indexers, copywriters, designers, and publishers. The online resource helps users find answers, apply consistent editorial standards, and prepare clear, well-crafted work.

Visitors can explore the manual’s contents and citation quick guide, consult Chicago Style Q&A, and browse the Shop Talk blog. The site also offers a user forum, video tutorials, and resources for librarians, teachers, and students. Subscriptions and a free trial provide access options, while the CMOS Store offers related products. The website includes information about the current 18th edition and the previous 17th edition, along with help and account-management tools. With more than 1.75 million copies sold, The Chicago Manual of Style has informed editorial practice for generations and brings its trusted guidance to an accessible online format.