What is PascalCase? Explained with Examples

What is PascalCase?

PascalCase (also called UpperCamelCase) is a naming convention where the first letter of every word is capitalized, with no spaces or separators between words.

Examples: MyClass, UserProfile, GetUserById, BackgroundColor

The name comes from the Pascal programming language, which popularized this style.

PascalCase in Programming

PascalCase is the standard convention for class names across virtually all object-oriented languages:

Language	What Uses PascalCase

|---|---|

Java	Class names, interfaces, enums (`UserService`, `HttpClient`)
C#	Classes, methods, properties, enums, namespaces
TypeScript	Interfaces, type aliases, enums (`UserProfile`, `ApiResponse`)
Python	Class names per PEP 8 (`MyClass`, `DatabaseConnection`)
React	Component names (`Button`, `UserCard`, `NavBar`)
Swift	Class names, structs, enums, protocols

PascalCase vs camelCase

Feature	PascalCase	camelCase

|---|---|---|

First letter	Uppercase	Lowercase
Example	`UserProfile`	`userProfile`
Used for	Classes, types, components	Variables, functions, methods
Also known as	UpperCamelCase	lowerCamelCase

Rule of thumb: In most languages, types use PascalCase; values use camelCase.

PascalCase in React

React has a very specific rule: all component names must use PascalCase.

This is not just a convention — it's enforced by React's rendering engine. A component named button would be treated as an HTML element. A component named Button is treated as a React component.

✓ — PascalCase — rendered as React component

✗ — lowercase — rendered as HTML (won't work)

Best Practices

Use PascalCase for all class names, even in languages that don't enforce it
Treat acronyms consistently — prefer XmlParser over XMLParser for readability
In React, always use PascalCase for component file names too — UserCard.tsx, not userCard.tsx

What is PascalCase? A Complete Explanation with Examples