💻 Text & Dev

🔡 🔡 Text Case Converter: UPPERCASE, lowercase, Title Case and More

Learn the different text cases and when to use each. Covers UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case, kebab-case, and PascalCase with usage rules.

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Text case — the pattern of uppercase and lowercase letters in text — is more than a stylistic choice. In writing, different cases signal different things (titles vs body text vs emphasis). In programming, naming conventions using specific cases are enforced by coding style guides and sometimes by compilers themselves. Knowing which case to use and when is a fundamental skill for both writers and developers.

The Major Text Cases

UPPERCASE (ALL CAPS)

Every letter is capitalized: HELLO WORLD

Use for: Acronyms (NASA, HTTP, URL), extreme emphasis, headings in some formal documents, constant names in some programming languages

Avoid: Running text — all caps significantly reduces readability and is perceived as shouting in digital communication

lowercase

Every letter is lowercase: hello world

Use for: Most programming variable names in languages like Python (snake_case), URL slugs, email addresses

Title Case

Major words are capitalized; minor words are not: "The Quick Brown Fox Jumps Over the Lazy Dog"

Title case rules (Chicago Manual of Style):

Capitalize: nouns, pronouns, verbs, adjectives, adverbs, and first/last words
Lowercase: articles (a, an, the), coordinating conjunctions (and, but, or), prepositions under 5 letters (in, on, at, by, for, of, to)
Always capitalize the first and last word regardless of part of speech

Use for: Article headlines, book titles, movie titles, webpage headings, product names

Sentence case

Only the first word and proper nouns are capitalized: "The quick brown fox jumps over the lazy dog"

Use for: Normal prose, email subjects (increasingly), social media posts, app UI labels and buttons (recommended by Google Material Design and Apple HIG for most UI text)

Alternating Case

Letters alternate between upper and lower: hElLo WoRlD

Use for: Mocking/sarcasm in informal contexts (the "mocking SpongeBob" meme format); no practical writing use

Programming Naming Conventions

Programming languages and style guides have strong conventions about which case to use for which type of identifier:

camelCase

First word lowercase, subsequent words capitalized, no spaces: myVariableName, getUserById

Used in: JavaScript variables and functions, Java variables and methods, Swift, JSON keys

PascalCase (UpperCamelCase)

Every word capitalized, no spaces: MyClassName, UserProfile, HttpRequest

Used in: Class names in most object-oriented languages (Java, C#, Python, Swift), React component names, TypeScript interfaces

snake_case

All lowercase, words separated by underscores: my_variable_name, user_id

Used in: Python variables and functions (PEP 8), Ruby, Rust, SQL column names, C language variables

SCREAMING_SNAKE_CASE

All uppercase with underscores: MAX_CONNECTIONS, DEFAULT_TIMEOUT

Used in: Constants in Python, C, Java, most languages — the convention for values that don't change

kebab-case

All lowercase, words separated by hyphens: my-variable-name, user-profile

Used in: CSS class names and IDs, HTML attributes, URL slugs, file names for web projects, npm package names

Case	Example	Primary Use
camelCase	myVariable	JS/Java variables
PascalCase	MyClass	Class names
snake_case	my_variable	Python, SQL
SCREAMING_SNAKE	MAX_SIZE	Constants
kebab-case	my-class	CSS, URLs, HTML

Capitalization Rules by Style Guide

Different style guides have different title case rules, which is why "The" and prepositions are handled inconsistently across publications:

Chicago Manual of Style: Most widely used in US publishing; lowercase prepositions under 5 letters
AP Style: Capitalize prepositions of 4+ letters (including "With," "From," "Into")
APA Style: Capitalize all words of 4+ letters
MLA Style: Lowercase all prepositions regardless of length

For blog headlines and web content, Chicago Manual of Style or AP style are most common. For academic papers, use whatever your institution requires.

Try It Yourself! ✨

Use our free Text Case Converter — results appear as you type. No sign-up needed!

🚀 Open Text Case Converter Free

❓ Frequently Asked Questions

What is Title Case and what are the rules?▼

Title Case capitalizes major words while leaving minor words lowercase. Per Chicago Manual of Style: capitalize nouns, pronouns, verbs, adjectives, adverbs, and always capitalize the first and last word. Lowercase: articles (a, an, the), short prepositions (in, on, at, by, for, of, to), and coordinating conjunctions (and, but, or, nor). Example: "The Cat in the Hat."

What is the difference between camelCase and PascalCase?▼

camelCase starts with a lowercase letter: myVariable, getUserById. PascalCase (also called UpperCamelCase) starts with an uppercase letter: MyClass, UserProfile. Both join words without spaces. camelCase is used for variables and functions in JavaScript and Java; PascalCase is used for class names in most OOP languages and for React component names.

What is snake_case and where is it used?▼

snake_case writes all words in lowercase separated by underscores: user_profile, get_user_by_id. It's the standard in Python (PEP 8 style guide) for variable names and functions, in Ruby, in Rust, and is common in SQL for column names. SCREAMING_SNAKE_CASE (all uppercase) is the convention for constants in most languages.

What is kebab-case?▼

kebab-case writes all words in lowercase separated by hyphens: my-component, user-profile. It's used in CSS class names and IDs, HTML data attributes, URL slugs (e.g., /blog/my-article-title), npm package names, and file names for web projects. It's called "kebab-case" because the hyphens look like skewers through the words.

When should I use Sentence case vs Title Case for headings?▼

Title Case is traditional for article headlines, book titles, and formal document headings. Sentence case (only first word and proper nouns capitalized) is increasingly preferred in modern UI design — Google Material Design and Apple's Human Interface Guidelines both recommend sentence case for most UI labels, buttons, and interface text. For blog headings, both are acceptable; pick one and be consistent.