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Camel Snake Converter🔒 100% local
Convert between camelCase and snake_case naming conventions.
Input
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Converts one identifier between camelCase and snake_case using a direction dropdown that doubles as a swap button. The camel-to-snake pass inserts an underscore before every capital letter and lowercases the rest; the snake-to-camel pass lowercases everything, splits on underscores and capitalises each part after the first. The transformation happens in the page.
How to use it
- Pick the direction from the dropdown, or press the arrow to reverse it.
- Paste the identifier into the input box.
- Press Convert, then copy the result.
Worked example
getUserProfileById (camel to snake)becomesget_user_profile_by_iduser_profile_id (snake to camel)becomesuserProfileIdHTTPServer (camel to snake)becomesh_t_t_p_serverThe rule fires per capital letter, so acronyms lose their grouping.
When to use it
- Renaming a JavaScript property to match a snake_case API payload.
- Reading a database column name back into a camelCase model field.
- Confirming the exact casing a style guide expects before committing a rename.
What it does not do
- There is no PascalCase direction. API_KEY becomes apiKey, and there is no way to get APIKey or ApiKey out of this tool.
- Acronyms do not round trip: HTTPServer becomes h_t_t_p_server and then hTTPServer.
- Only underscores count as separators going back, so user-profile-id or a spaced name stays in one word with a capital at the front.
- A leading underscore is dropped: _privateField comes back as private_field.
- No input is rejected, so text that is already snake_case passes through camel-to-snake unchanged and looks like a successful conversion.