✍️ Writing & Style Guide

Title Case vs Sentence Case: When to Use Each & Full Rules Explained (2026)

📅 May 2026⏱ 9 min read✍️ ToolLoom Editorial

Should your blog post heading read "How to Write Better Headlines" or "How to write better headlines"? The answer depends on your style guide, your audience, and the type of content you're writing. This guide explains the full rules for both cases — and when each one is the right choice.

📋 In This Article
  1. Title case vs sentence case — the core difference
  2. Full rules for title case
  3. Full rules for sentence case
  4. AP, Chicago, APA, MLA — which uses which?
  5. When to use each style
  6. Tricky words and edge cases
  7. Common capitalisation mistakes
  8. Frequently asked questions

Title Case vs Sentence Case — The Core Difference

The fundamental distinction is simple: title case capitalises most words; sentence case capitalises only the first word and proper nouns.

🔤 Title Case

"How to Write Better Headlines for Your Blog"
  • Capitalise major words (nouns, verbs, adjectives, adverbs)
  • Lowercase minor words (a, an, the, and, but, or)
  • Always capitalise first and last word
  • Used in headlines, book titles, film names

🔡 Sentence Case

"How to write better headlines for your blog"
  • Capitalise only the first word of the heading
  • Capitalise proper nouns anywhere they appear
  • All other words remain lowercase
  • Used in UI, blogs, academic writing, emails
💡

Neither style is universally "correct." The right choice depends entirely on your style guide, publication, brand voice, and context. Consistency within a document or publication is more important than which style you pick.

Full Rules for Title Case

Title case sounds simple but has surprisingly complex rules around which words to capitalise and which to leave lowercase. Here are the complete rules:

Always capitalise

Always lowercase (unless first or last word)

⚠️

Longer prepositions are capitalised. "Through", "Between", "Among", "Without", "Throughout" — prepositions of 5+ letters are typically capitalised in title case under Chicago and AP style.

Real examples

Title Case ✓
The Quick Brown Fox Jumps Over the Lazy Dog
Title Case ✓
What Is the Best Way to Learn a New Skill?
Title Case ✓
Running Through the Fields and Into the Night
Title Case ✓
How to Start a Business With No Money

Full Rules for Sentence Case

Sentence case is simpler than title case — but there are still a few rules to get right.

Capitalise

Do NOT capitalise

Real examples

Sentence Case ✓
The quick brown fox jumps over the lazy dog
Sentence Case ✓
How to use Google Sheets for budgeting in India
Sentence Case ✓
What is the best EMI calculator for home loans?
Sentence Case ✓
Running through the fields and into the night

AP, Chicago, APA, MLA — Which Uses Which?

AP Style
Journalism, news, press releases
Title case for headlines. Lowercase prepositions and conjunctions under 4 letters. Widely used in Indian English media.
Chicago Style
Books, publishing, editorial
Title case for titles. Capitalise prepositions of 5+ letters. The most detailed and nuanced title case rules of any guide.
APA Style
Academic, psychology, social sciences
Title case for article titles in references. Sentence case for headings within the paper body. A common source of confusion.
MLA Style
Literature, humanities, schools
Title case for titles of works cited. Sentence case for headings within the essay body.
Google / Tech Style
Tech docs, UI, product copy
Sentence case for almost everything — UI buttons, menu items, headings, product names. Title case only for proper product names.
Microsoft Style
Software, docs, UI
Sentence case for UI elements and headings. Title case only for product and feature names. Similar to Google's approach.
💡

The modern trend is toward sentence case. Most major tech companies (Google, Microsoft, Apple, Notion, Figma) now use sentence case for UI and product copy. It reads as more natural and conversational — which aligns with modern content design principles.

When to Use Each Style

ContextRecommended StyleReason
Book and film titlesTitle CasePublishing convention — formal titles use title case globally
News article headlinesTitle CaseAP style — standard in newspapers and news websites
Blog post headings (H2, H3)Sentence CaseMore readable, modern web style, matches conversational tone
Blog post title (H1)EitherDepends on brand — both are widely used. Be consistent.
UI buttons and menusSentence CaseGoogle, Microsoft, Apple all use sentence case for UI elements
Academic paper titlesTitle CaseAPA, MLA, Chicago all use title case for work titles
Academic paper headingsSentence CaseAPA and MLA use sentence case for section headings within the paper
Email subject linesSentence CaseMore natural and less formal — reads like a human wrote it
Social media postsSentence CaseConversational platforms — title case looks stiff and robotic
Product names and brand namesTitle CaseProper nouns — always capitalised regardless of surrounding style

Tricky Words and Edge Cases

Hyphenated words in title case

Hyphenated compound words are one of the trickiest areas. The Chicago Manual of Style says capitalise both parts if both are major words. AP says capitalise only the first part unless the second is a proper noun.

Chicago Title Case
The Step-By-Step Guide to Long-Term Planning
AP Title Case
The Step-by-Step Guide to Long-term Planning

"Is", "Are", "Be" — short verbs always capitalised

Even though these are short words, they are verbs — and verbs are always capitalised in title case. This trips up many writers who think length determines capitalisation.

Correct ✓
What Is the Best Diet for Indians?
Wrong ✗
What is the Best Diet for Indians?

"That" vs "which" — both capitalised in title case

"That" and "which" function as pronouns or subordinating conjunctions — both are capitalised in title case under Chicago and AP style.

Proper nouns in sentence case

Even in sentence case, proper nouns must be capitalised. This includes: names of people (Virat Kohli), places (Mumbai, India), languages (Hindi, Tamil), brands (Google, Amazon, WhatsApp), and official names (Government of India, Supreme Court).

Common Capitalisation Mistakes

✗ Wrong: "The best Tips For Writing Better"
✓ Right: "The Best Tips for Writing Better"
Rule: "for" is a short preposition/conjunction — lowercase in title case. "Tips" and "Best" are noun and adjective — capitalised.
✗ Wrong: "How to use google sheets"
✓ Right: "How to use Google Sheets"
Rule: Even in sentence case, proper nouns and brand names must be capitalised. Google Sheets is a proper product name.
✗ Wrong: "A guide to bmi calculators in india"
✓ Right: "A guide to BMI calculators in India"
Rule: Acronyms (BMI) and country names (India) are proper nouns — always capitalised even in sentence case.
✗ Wrong: "10 Ways To Save Money Every Month"
✓ Right: "10 Ways to Save Money Every Month"
Rule: "to" in an infinitive ("to Save") is lowercase in title case. The verb "Save" is capitalised, but "to" is not.
✗ Wrong: "the quick brown fox" (sentence case)
✓ Right: "The quick brown fox"
Rule: In sentence case, the very first word is always capitalised — even if it's "the", "a", or any other article.

🔤 Convert Text to Title Case or Sentence Case Instantly

Free case converter tool — paste any text and convert to Title Case, Sentence case, UPPER CASE, lower case, or camelCase in one click.

Open Case Converter →

Frequently Asked Questions

Title case capitalises the first letter of most words — specifically all major words (nouns, verbs, adjectives, adverbs) while leaving minor words (articles, short prepositions, conjunctions) lowercase. Sentence case only capitalises the first word of the heading and any proper nouns. "How to Write Better Content" is title case; "How to write better content" is sentence case.
Articles (a, an, the), coordinating conjunctions (and, but, or, nor, for, so, yet), and short prepositions (at, by, for, in, of, on, to, up, via) are lowercase in title case — unless they are the first or last word of the title. Prepositions of 5 or more letters (Through, Between, Among, Without) are typically capitalised under Chicago style.
There is no universal rule, but the modern trend in web content is toward sentence case for blog headings (H2, H3 and below) because it reads as more natural and conversational. Many major publications including HubSpot, Buffer, and Moz use sentence case for subheadings. For the main blog title (H1), either style works — just be consistent throughout your site.
APA style uses both, in different contexts. For references (bibliography entries), APA uses sentence case for article and chapter titles, but title case for journal names and book titles. For headings within the body of a paper, APA uses title case for Level 1 and Level 2 headings, and sentence case for Level 3, 4, and 5 headings. This is one of the more nuanced style guide distinctions.
Yes — always. "Is", "are", "be", "do", "go", and other short verbs are always capitalised in title case because they are verbs, not minor words. Part of speech determines capitalisation in title case, not word length. "What Is the Best Way to Learn?" is correct title case — "is" is capitalised because it's a verb.
Sentence case is generally preferred for email subject lines in modern communication. It reads as more natural and human — which is particularly important for marketing emails where you want to avoid looking like a mass-blast promotional message. Title case can work for formal business correspondence, but most email marketing research suggests sentence case performs better for open rates.

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