Title Case vs Sentence Case: Which One Your Document Needs

What each style actually does

Think of the two styles as two different signals. Title case signals "this is a headline" and makes a heading stand out, which is why books and formal reports have used it for so long. Sentence case signals "this reads like a normal sentence" and feels quieter, which is why so many apps and email inboxes now use it for labels and subjects.

Here is the same heading in both styles, so you can feel the difference at a glance:

Neither style is more correct in general. A style is correct when it matches the rules of the document you are writing, so the question is not "which style is better?" but "which style does this document ask for?"

Title case is not the same as capitalizing every word. A tool that capitalizes every word turns "The Lord of the Rings" into "The Lord Of The Rings", and that middle "Of" is wrong under most headline rules.

Title case rules, in plain language

Different style guides disagree on small details, but the core of title case is stable. The APA rules below are a good default, because many schools and workplaces follow them or something close. If your publisher gives you its own guide, that guide wins.

Capitalize these words in title case:

• The first word of the title or heading, even if it is a small word such as "The" or "A".
• The last word of the title or heading.
• The first word after a colon, because it starts a subtitle. "How to Write Better Headlines: A Short Guide" keeps "A" capitalized after the colon.
• Major words: nouns, verbs (including linking verbs such as "is" and "are"), adjectives, adverbs and pronouns.
• Words of four letters or more, even if they are prepositions. That is why "With", "Between" and "From" take capitals in APA title case.
• Both parts of a hyphenated major word. Write "Self-Report", not "Self-report".

Leave these words lowercase, but only when they sit in the middle of the title:

• Articles: "a", "an" and "the".
• Short conjunctions of three letters or fewer: "and", "as", "but", "for", "if", "nor", "or", "so" and "yet".
• Short prepositions of three letters or fewer: "at", "by", "in", "of", "off", "on", "per", "to", "up" and "via".

A handy shortcut: if a word is three letters or fewer and it is not a noun, verb, adjective, adverb or pronoun, leave it lowercase in the middle of a title. Checking "and", "of" and "the" first catches most errors.

Chicago and AP headline styles follow the same idea, with small differences around prepositions. For everyday headings the guides agree far more often than they disagree, so pick one and apply it evenly.

Proper nouns and brand names keep their official spelling in every style. "iPhone" stays "iPhone" and "YouTube" stays "YouTube", even in sentence case. Never "fix" a brand name to fit a pattern.

Sentence case rules, in plain language

Sentence case is simpler, which is one reason it has spread so fast in apps and on the web. Capitalize only these words:

• The first word of the title or heading.
• The first word after a colon, because it starts a subtitle.
• Proper nouns, wherever they appear: names of people, places, organizations and brands.
• Nouns followed by a number or letter, such as a test name with a version number, where the style guide asks for it.

Everything else stays lowercase, including major words that title case would capitalize. In "The best free tools for writers and students", the words "best", "free" and "tools" stay lowercase. That is the rule, not laziness, and capitalizing them turns the heading back into title case.

Sentence case also applies inside APA reference lists, where students lose marks most often. The title of an article, book or webpage is written in sentence case even if the original used title case, while the journal or newspaper name stays in title case. One reference line can correctly contain both styles at once:

Smith, J. (2024). How to write better headlines. The Journal of Clear Writing. The article title is in sentence case. The journal name is in title case. If you title-case both, the reference is wrong under APA rules, even though it looks tidier to some eyes.

One trap in sentence case is the first word after a colon. In a title or heading it starts a subtitle, so it takes a capital in both styles: "How to write better headlines: A short guide" keeps "A" capitalized in both.

When to use title case and when to use sentence case

Use this table as your first decision, then check the specific guide for the place you are writing for. When they disagree, the guide wins.

If you write for a team, add a one-line style note at the top of your shared document: "Headings in title case (APA), reference titles in sentence case." That line prevents the drift where three editors produce three styles in one report. For a personal blog with no guide, use title case for post titles and sentence case for email subjects and social captions, which matches what most readers already expect.

Side-by-side examples

Each pair shows the same words in both styles, with a note on the detail that decides the answer.

Read the "Detail to notice" column, not just the two versions. After ten headings, the checks become automatic: first word, last word, major words, small words in the middle, proper nouns, word after a colon.

How to convert text in 4 steps

Fixing headings by hand is fine for one title. For a whole essay or a report with forty headings, a converter saves you from retyping and from new typos. The steps below use the free Case Converter tool on this site.

1. Paste your text into the Case Converter. Open the free Case Converter tool and paste the headings or paragraphs you need to fix. You can paste a whole block at once; you do not need to convert one heading at a time.
2. Pick Title Case or Sentence case. Choose Title Case for formal headings and titles, or Sentence case for reference entries, subjects and interface text. The tool also offers UPPERCASE, lowercase, alternating, inverse, slugify and fix spacing, but for this job you only need the two heading styles.
3. Copy the result back into your document. Copy the converted text and paste it where it belongs, then save. If you pasted a whole document, check that paragraph breaks survived the round trip before you move on.
4. Check the small words by hand. This is the honest limit of a bulk converter. The Case Converter page itself warns that its Title Case capitalizes small words too, so scan each heading for "and", "or" and "of" in the middle, lowercase them where the rule asks for it, and check proper nouns at the same time.

That last check takes about thirty seconds for a normal document, and it turns a mechanical conversion into a correct one. You handle the judgment calls a converter cannot: is this "and" in the middle of a title, is "iPhone" spelled right, does a subtitle start after a colon?

Common mistakes and fixes

Most case errors come from the same few habits. Fix the habit and the headings get easier.

The pattern behind all six is the same: readers trust documents where the case signal stays steady. A converter plus a short manual check is the cheapest way to avoid a mixed-style impression.

Try the case converter free

Stop retyping headings one by one. Open the free Case Converter tool, paste your text, pick Title Case or Sentence case, and run the thirty-second small-word check before you submit.

How we tested this: we read the Case Converter tool page on this site and confirmed it offers UPPERCASE, lowercase, Title Case, Sentence case, alternating, inverse, slugify and fix spacing, with no signup, and that its own page warns Title Case capitalizes small words too. We checked the APA rules against the APA Style pages for title case and sentence case capitalization.

Privacy note: the Case Converter on this site needs no account and no signup. You paste text into the page, convert it, and copy the result back into your own document.

Last updated: October 26, 2026