camelCase vs PascalCase — Which Should You Use?
Compare camelCase and PascalCase naming conventions. Learn when to use each in your code and why the distinction matters.
| Feature | camelCase | PascalCase |
|---|---|---|
| First letter | Lowercase | Uppercase |
| Typical use | Variables, functions, methods | Classes, types, interfaces, React components |
| JavaScript/TypeScript | Variables and functions | Classes, types, React components |
| C# | Private fields, parameters | Classes, methods, properties (all public) |
| Example | getUserById | UserService |
Verdict
In most languages, use camelCase for variables, parameters, and private members, and PascalCase for classes, types, and constructors. They are complementary rather than competing conventions. Following your language's standard makes your code instantly recognizable to other developers.
Two Sides of the Same Coin
camelCase and PascalCase are not competing conventions but complementary ones. Almost every language uses both: camelCase for values (variables, functions) and PascalCase for types (classes, interfaces). The casing itself carries semantic meaning, helping developers instantly understand what kind of identifier they are looking at.
Frequently Asked Questions
React uses the casing to distinguish between HTML elements and custom components. Lowercase names (div, span) are treated as HTML elements, while PascalCase names (MyComponent) are treated as React components.
Yes. PascalCase and UpperCamelCase refer to the same convention. PascalCase is the more commonly used term, named after the Pascal programming language.