Snake Case Converter

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Turn camelCase, kebab-case, PascalCase or plain sentences into snake_case, with an option for SCREAMING_SNAKE_CASE constants.

Privacy: This tool runs entirely in your browser. Your input never leaves your device.

How to use Snake Case Converter

  1. Paste identifiers, one per line.
  2. Enable SCREAMING_SNAKE_CASE for constants if needed.
  3. Copy the converted list.

Snake Case Converter features

  • Converts camelCase, PascalCase, kebab-case and sentences to snake_case
  • SCREAMING_SNAKE_CASE option for constants and environment variables
  • Acronym boundaries detected (HTTPResponseCode → http_response_code)
  • Batch conversion with an input/output table
  • Unicode letters preserved

Snake Case Converter example

Python names from JavaScript identifiers

Input:

userFirstName
HTTPResponseCode
max-retry-count

Output:

user_first_name
http_response_code
max_retry_count

Frequently asked questions about Snake Case Converter

When should I use snake_case?

Python variables and functions, Ruby, Rust, database columns and many REST APIs use snake_case. Environment variables and constants usually use the upper-case variant.

How do I get SCREAMING_SNAKE_CASE?

Tick the "SCREAMING_SNAKE_CASE" option; every word is upper-cased and joined with underscores, e.g. MAX_RETRY_COUNT.

Does "HTTPResponseCode" become http_response_code?

Yes. Acronyms are detected as separate words, so the result is http_response_code rather than h_t_t_p_response_code.

Are non-Latin letters preserved?

Yes — Arabic, Devanagari and other letters are kept as words and joined with underscores; only the separators change.