Title Case vs sentence case: which one to use and when

Capitalization looks like a detail until a page mixes three styles in its headings. Picking one style, and applying it consistently, makes text easier to scan. Here is what the two main options do.

The two styles

Sentence case capitalizes the first word and proper nouns only, exactly like a normal sentence: “How to choose a laptop for university”.

Title Case capitalizes the main words and leaves certain short words lowercase: “How to Choose a Laptop for University”.

A third option, capitalizing every word (“How To Choose A Laptop For University”), is not a recognized editorial style. It is common on social media but reads as less polished in headings.

The small-word problem

Style guides agree on capitalizing nouns, verbs, adjectives and adverbs. They disagree on short words:

• Chicago Manual of Style lowercases articles (a, an, the), coordinating conjunctions (and, but, or, for, nor) and all prepositions regardless of length, so “Through” becomes “through”.
• AP style lowercases articles, short conjunctions and prepositions of three letters or fewer, but capitalizes longer prepositions such as “With” and “From”.
• Both capitalize the first and last word of a title, whatever it is.

Toolora’s Title Case follows the shorter rule: it lowercases articles, coordinating conjunctions and prepositions of up to three letters, capitalizes the first and last word, and capitalizes the word after a colon. That matches AP closely and Chicago in most everyday titles. If you follow Chicago strictly, check longer prepositions such as “with”, “from” and “into” by hand.

When to use each

• Sentence case suits interfaces, buttons, help articles and most web headings. It is easier to read, avoids style debates, and is the default in many digital style guides, including GOV.UK’s.
• Title Case suits book and film titles, the titles of articles in some publications, and academic references where the citation style requires it.
• For essays and assignments, the citation style decides. APA, for example, uses Title Case for the title of your paper and sentence case for the titles of works in the reference list.

Edge cases worth checking by hand

• Brand names and acronyms. “iPhone”, “NASA” and “JSON” keep their own capitalization. The converter leaves words that already contain capitals after the first letter untouched in Title Case, but Sentence case and lowercase will flatten them.
• Hyphenated words. Most styles capitalize both parts (“Well-Known”); Chicago keeps some prefixes lowercase (“Anti-inflammatory”).
• Words that change role. “Up” is a preposition in “up the hill” but part of a verb in “Set Up Your Account”, where it should be capitalized. Automatic tools cannot tell the difference.