snake_case Converter
Convert phrases and identifiers into snake_case — common in Python and databases.
Input
Convert to
Output
Private by design
This conversion runs entirely in your browser. Your text is not sent to a server.
Tip
Passwords, API keys, and some identifiers are case-sensitive. Convert them only when you intend to change the value.
How to convert with snake_case Converter
Paste or type your text in the input box.
Watch the output update instantly — nothing is uploaded.
Pick another case style to open that converter with the same text.
Copy the result, or use it as the next input.
When should you use it?
Writing
Soften headlines, notes, and chat so the copy reads as normal sentences.
Programming
Match identifier conventions in code, configs, and APIs.
URLs
Prepare hostnames, paths, slugs, and CSS class names.
Data
Normalize names, tags, and imported rows to a single case.
About snake_case conversion
snake_case lowercases words and joins them with underscores. It is common in Python, JSON field names, and databases. kebab-case uses hyphens instead; CONSTANT_CASE uses underscores but stays uppercase.
Worked example: “The Quick BROWN Fox” becomes “the_quick_brown_fox.” Leading digits and odd punctuation may be dropped or glued — check the output before you rename a column.
Nothing is uploaded. Related: kebab-case, camelCase, CONSTANT_CASE, Slugify for URL-safe strings with accent folding.
The URL is /tools/snake-case. This is not a SQL migration and not a uniqueness check. Double underscores from messy input are possible — tidy the source if the column name looks wrong. Python modules often use this style; CSS classes usually want kebab-case.
ORMs still need a real migration. This box only rewrites the string you pasted.
snake_case Converter examples
Headline
Sentence
Identifier
Case style comparison
| Style | Example | Typical use |
|---|---|---|
| lowercase | hello world example | Soft copy, tags, and normalizing user input |
| UPPERCASE | HELLO WORLD EXAMPLE | Headings, acronyms, and short labels |
| Sentence case | Hello world example | Prose, captions, and readable paragraphs |
| Title Case | Hello World Example | Titles, headlines, and proper names |
| camelCase | helloWorldExample | JavaScript variables and object keys |
| PascalCase | HelloWorldExample | Types, classes, and React components |
| snake_case | hello_world_example | Python, APIs, and database columns |
| kebab-case | hello-world-example | URLs, CSS classes, and file names |
| CONSTANT_CASE | HELLO_WORLD_EXAMPLE | Env vars, constants, and enum names |
snake_case Converter FAQ
Both lowercase words. snake_case joins with underscores (Python, JSON fields, databases). kebab-case joins with hyphens (URLs, CSS). CONSTANT_CASE uses underscores but stays uppercase. Example: “The Quick BROWN Fox” becomes “the_quick_brown_fox.”
Leading digits and odd punctuation may be dropped or glued. Check the output before you rename a column. Slugify is the sibling when the source is a headline with accents.
No. Conversion runs locally. Convert to keeps input across camelCase and CONSTANT_CASE. Nothing is uploaded.
No. It does not check uniqueness in a database. Double underscores from messy input are possible — tidy the source. Python modules often use snake_case; CSS classes usually want kebab-case. Close the tab to drop the draft. Nothing is uploaded.