Free Online snake_case Converter

snake_case joins words with underscores and lowercases everything ("hello world" becomes "hello_world") — the standard convention in Python, SQL column names and many config formats.

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How to Use This Text Tool

  1. Paste a phrase or label into the input field.
  2. The snake_cased version appears in the output panel.
  3. Click Copy to paste it into your code or config file.

What Is a snake_case Converter?

Python's PEP 8 mandates snake_case for variable and function names. Postgres, MySQL and many ORMs default to snake_case column names. The format is also a safe choice for filenames because underscores survive every shell and filesystem unchanged, unlike spaces or hyphens.

The converter splits on whitespace and punctuation, lowercases every segment, and joins them with underscores. Numbers are preserved in place. "User First Name 2" becomes "user_first_name_2".

For URL slugs or CSS class names, use kebab-case (hyphens) instead. For constants and environment variables, use CONSTANT_CASE (uppercase with underscores).

Frequently Asked Questions

What is snake_case?
snake_case uses underscores between words, all lowercase (e.g., 'hello world' → 'hello_world'). Named for the visual 'snake' of underscores.
When to use snake_case?
Python uses snake_case for variables and functions. Databases often use it for column names. It's also common in file names and config keys.
snake_case vs kebab-case?
snake_case uses underscores (hello_world); kebab-case uses hyphens (hello-world). Kebab-case is common in URLs and CSS; snake_case in Python and SQL.

Published by the WeGotEveryTool team. We build and test every tool in-house and update pages when the underlying spec, formula, or recommendation changes.

Reviewed: May 2026. Disclaimer: this tool is provided as-is for general informational use. For decisions with material consequences (medical, legal, financial, security) verify results against a qualified professional source.

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