Sentence case vs. title case

What the two cases are

Sentence case follows the rules of a normal sentence: capitalize the first word and any proper nouns, and lowercase everything else ("How to reset your password"). Title case capitalizes the principal words — nouns, verbs, adjectives, adverbs, and pronouns — while leaving short articles, conjunctions, and prepositions lowercase unless they are first or last ("How to Reset Your Password"). There is also all-caps and the rarely-recommended "Start Case" that capitalizes every word including small ones; both are usually avoided in body and heading copy.

Title case has competing rule sets — the Chicago, AP, and APA styles disagree on which short words to capitalize and at what length — which is part of why it is harder to apply consistently. Sentence case has essentially one rule, which is one reason many modern style guides, especially in software and product design, have moved toward it for headings, buttons, and UI labels.

Why it matters for website copy

Capitalization style is one of the most visible consistency choices on a site, because headings and buttons appear on every page. A site that uses sentence case for one heading ("Browse our plans") and title case for the next ("Start Your Free Trial") looks as though two people built it without agreeing on a standard — which is usually exactly what happened. Neither case is wrong; the mismatch between them is the error.

The decision is a style choice, and the discipline is consistency: pick one convention for headings, one for buttons, one for navigation, and apply each everywhere. This is squarely a matter of style and internal agreement — the kind of thing a proofreading pass surfaces when one page disagrees with another. Verant reads style as one of its six kinds of copy issue, flagging copy that reads inconsistently from page to page; it does not, however, enforce a configured house-style rule that headings must be sentence case — there is no style guide to load — so the judgment is about the copy agreeing with itself rather than conforming to a specific external standard.

Common mistakes

The most common mistake is having no agreed convention, so headings drift between the two cases across the site. Another is mixing them within a single interface — sentence-case page headings but title-case buttons — without that being a deliberate, documented choice. A third is applying title case inconsistently because its rules are fiddly: capitalizing a preposition on one heading and lowercasing it on the next ("Sign Up for Free" vs. "Sign up For Free"). The cleanest answer is usually to choose one case, prefer the simpler rule where you can, and apply it uniformly.