snake_case Converter

Paste names or phrases and get lowercase snake_case, one per line.

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The text hello world converted between lowercase, UPPERCASE and Title Case

About snake_case

snake_case writes everything in lowercase with underscores between words: userFirstName becomes user_first_name. It is the convention for variables and functions in Python (PEP 8), Ruby and Rust, and is popular for database table and column names.

Capital letters inside camelCase words are treated as word boundaries, so you can paste a whole list of JavaScript property names and get database-friendly columns.

Need more options? Open the full Case Converter.

Frequently asked questions

What is snake_case used for?

Variable and function names in Python, Ruby and Rust, and column names in SQL databases.

How do I convert camelCase to snake_case?

Paste the names above. Capital letters are treated as word boundaries and replaced by underscores.

What is SCREAMING_SNAKE_CASE?

The uppercase version, used for constants. Choose CONSTANT_CASE in the main case converter.

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