When you first learn how to code, one of the earliest problems you encounter is how to name user variables, functions, and classes. In programming, identifiers cannot contain spaces because the compiler (or interpreter) would see multiple disconnected words and throw syntax errors. To circumvent this, software engineers developed various naming conventions.
Choosing the right naming convention—and strictly adhering to it—improves code readability, maintains consistency within a team, and aligns with community standards for specific programming languages. Let’s break down the big four: camelCase, PascalCase, snake_case, and kebab-case.
1. camelCase (dromedaryCase)
Considered one of the most widely used naming conventions today, camelCase gets its name from its appearance: the capital letters in the middle of a word look like the humps of a camel.
- Rule: The first letter of the first word is strictly lowercase. The first letter of every subsequent appended word is capitalized. No spaces or underscores are used.
- Example:
userFirstName,calculateTotalSum,isLoggedIn
Where is camelCase used?
It is predominantly the standard for naming variables, objects, and functions in languages like Java, JavaScript, TypeScript, C++, and Swift.
2. PascalCase (UpperCamelCase)
PascalCase is a sibling to camelCase. In fact, many people often confuse the two. The distinction lies entirely in the very first letter.
- Rule: The first letter of every word is capitalized, including the very first word. No spaces or underscores.
- Example:
UserFirstName,CalculateTotalSum,AccountManager
Where is PascalCase used?
In almost all modern programming languages (such as C#, Java, Python, and JavaScript), PascalCase
is strictly reserved for naming Classes, Constructors, and Interfaces. For example, in React (a
JavaScript library), components must be defined using PascalCase (e.g.,
<NavigationBar /> over <navigationBar />).
3. snake_case
If you have ever written a line of Python, Ruby, or SQL, you are intimately familiar with snake_case. This convention eliminates capital letters entirely in favor of an underscore to separate words.
- Rule: All letters are formatted to lowercase. Spaces are replaced by an
underscore (
_) character. - Example:
user_first_name,calculate_total_sum,is_logged_in
Variations of snake_case
A notable variation is SCREAMING_SNAKE_CASE (also known as MACRO_CASE). In this
style, every letter is capitalized, and underscores separate the words. Across nearly all coding
languages, SCREAMING_SNAKE_CASE is universally recognized as the standard for defining
Constants (e.g., MAX_FILE_SIZE = 1024).
4. kebab-case (dash-case)
Visually, kebab-case looks like words skewed together on a shish kebab skewer.
- Rule: All letters are formatted to lowercase. Spaces are replaced by a
hyphen or dash (
-). - Example:
user-first-name,nav-bar-section,submit-btn
Where is kebab-case used?
You cannot use kebab-case for variable naming in most standard programming languages (like JS or
Python) because the compiler reads the hyphen as a minus (subtraction) mathematical operator:
user - first - name.
Instead, kebab-case is the absolute standard in:
- HTML and CSS: Used for class names and IDs (e.g.,
class="header-container"). - URLs and Slugs: When generating permalinks for a website, kebab-case is the
most SEO-friendly formatting option (e.g.,
www.example.com/blog/how-to-code).
Need to Format Names Quickly?
If you're converting a bulk database of strings or updating messy code, doing this manually is annoying. To save time, you can put your string directly into our tool and instantly click "camelCase", "snake_case", or "kebab-case" to convert your text automatically.