Case Converter · snake_case
snake_case Converter
Lowercase words, joined by underscores: the naming convention of Python, Ruby and most databases. Paste a label or a camelCase identifier and get clean snake_case back.
Tip: select part of your text first and only the selection is converted. Conversions happen in place and are fully undoable here — nothing leaves your browser.
Examples
| Input | snake_case | SCREAMING_SNAKE_CASE |
|---|---|---|
| user profile last login | user_profile_last_login | USER_PROFILE_LAST_LOGIN |
| helloWorldExample | hello_world_example | HELLO_WORLD_EXAMPLE |
| Max Retry Count | max_retry_count | MAX_RETRY_COUNT |
Existing case boundaries are respected, so converting between developer formats is lossless for ordinary identifiers: camelCase splits at its humps, kebab-case at its hyphens, and nothing comes out with double underscores.
snake_case or SCREAMING?
Plain snake_case is for variables, functions and columns — things whose value can change. The all-caps SCREAMING_SNAKE_CASE is the near-universal signal for constants and environment variables — things set once. Both are one click apart in the tool above; the developer formats page puts them next to camelCase, PascalCase, kebab-case and dot.case.
FAQ
- What happens to numbers?
- They stay attached to the word they follow — “version 2 name” becomes
version_2_namewhen the 2 stands alone, and “oauth2 token” keeps its 2 inline asoauth2_token. - Does it remove punctuation?
- Punctuation acts as a word separator and disappears — that is what makes the output a valid identifier.
- Can it convert back to camelCase?
- Yes — paste the snake_case text and click camelCase.
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