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Pascal case vs. camel case: What's the difference?

It's easy to confuse camel case and Pascal case. We'll show you the difference between the two common variable naming conventions, along with some examples.

Variable naming conventions are important. Any time a developer learns a new language or low-code tool, one of the first topics they seek clarification on is the standardized naming conventions. Pascal case and camel case are two of the most often referenced.

Camel case and Pascal case are similar. Both demand variables made from compound words and have the first letter of each appended word written with an uppercase letter. The difference is that Pascal case requires the first letter to be uppercase as well, while camel case does not.

Pascal case examples

The below examples follow both camel case and Pascal case naming conventions:

  • OutOfMemoryException
  • DateFormat
  • DatabaseConnection
  • LinkedList
  • EventHandler

Pascal case is always consistent with camel case rules. However, when a variable starts with a lowercase letter, camel case is not consistent with Pascal case.

Camel case examples

The following camel case examples do not follow the Pascal case convention:

  • jenkinsServer
  • iterationCount
  • tomcatInstance
  • gitRepository
  • microService

The term "lower camel case" is often used when a variable starts with a lowercase letter (jenkinsServer), while "upper camel case" is often used to refer to variables that comply to Pascal case rules (JenkinsServer).

Camel case vs. pascal case usage

Most languages and development frameworks distinguish between the types of components that should be written in a given naming format. For example in Java, classes, interfaces and enums should all be written in Pascal case. Local variables declared within the body of a Java program should be written in lower camel case.

Variable naming convention alternatives

Alternatives to Pascal case and camel case include kebab case, where a dash separates words, and snake case, where an underscore is used.

  • this-is-kebab-case

Many programming languages, including C++ and Java, use snake case for constants and static variables. The use of kebab case tends to be discouraged, as the dash can be misread as a subtraction operation.

In most development environments, the use of Pascal case versus camel case is a convention, not a necessity. Code will still compile and run, regardless of which naming convention is used. The proper use of Pascal case and camel case is intended to make code more readable and maintainable. It is not a compiler requirement.

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