snake_case Converter
Convert text or identifiers to snake_case instantly.
This tool runs entirely in your browser. Your files are never uploaded to a server.
Convert a word sequence to lowercase snake_case joined by underscores. Tokenization splits whitespace, `_`, `-`, `.`, `/`, lowercase-to-uppercase boundaries, and an acronym before its following capitalized word, so `APIResponse/user-id` becomes `api_response_user_id`. Repeated supported separators collapse, while other punctuation can remain attached to a token. Original capitalization and acronym styling are discarded. The result is generated locally for copying and does not validate reserved words or identifier rules for any programming language, database, or API.
Frequently Asked Questions
- What is snake_case used for?
- It's the standard naming convention for variables and functions in Python and Ruby, and for column and table names in most SQL databases.
- Can I convert from camelCase or kebab-case to snake_case?
- Yes — the tool splits your input on hyphens, dots, spaces, and existing camelCase/PascalCase boundaries before rejoining it with underscores, so it works from any of those styles.
- What's the difference between snake_case and CONSTANT_CASE?
- Both join words with underscores, but snake_case keeps every letter lowercase while CONSTANT_CASE uppercases every letter — used for constants and environment variables.