camelCase vs snake_case: Which Should You Use?

·4 min read

What Is camelCase?

camelCase is a naming convention where the first word is lowercase and each subsequent word starts with an uppercase letter. There are no spaces or separators between words.

Examples: myVariableName, getUserData, totalItemCount

What Is snake_case?

snake_case uses all lowercase letters and separates words with underscores. It is easy to read and widely used in several programming languages.

Examples: my_variable_name, get_user_data, total_item_count

Key Differences

FeaturecamelCasesnake_case
Word separatorCapital letterUnderscore
CaseMixedAll lowercase
Common inJavaScript, Java, C#Python, Ruby, SQL

When to Use camelCase

camelCase is the dominant convention in:

  • JavaScript and TypeScript — for variable and function names
  • Java and C# — for methods and local variables
  • JSON keys — widely adopted in REST APIs

When to Use snake_case

snake_case is preferred in:

  • Python — the official PEP 8 style guide recommends snake_case for variables and functions
  • Ruby — snake_case is the standard for all identifiers
  • SQL — column and table names commonly use snake_case
  • Rust — snake_case for variable and function names

Quick Conversion Tool

Need to switch between formats? Use our camelCase converter or snake_case converter to instantly transform your text.