Snake Case Converter — Convert Text to snake_case Online Free
Instantly convert any text to snake_case — all lowercase with underscores between words. The standard naming convention for Python, SQL, Ruby, and database columns. Handles camelCase and PascalCase input too.
When to Use snake_case
snake_case is one of the most widely used naming conventions in software development and data management. Here is where it is required or expected.
PEP 8 — the official Python style guide — mandates snake_case for all variable names, function names, method names, and module names in Python code.
snake_case is the widely accepted standard for SQL table names, column names, and index names across PostgreSQL, MySQL, SQLite, and most relational databases.
Ruby on Rails uses snake_case for method names, variable names, database column names, and file names throughout the framework by convention.
Many REST APIs return JSON with snake_case field names, particularly those built with Python (Django, FastAPI, Flask) or Ruby on Rails backends.
snake_case is standard for naming files in Python projects, Linux systems, and open-source codebases where spaces in filenames cause issues.
Quickly convert variable names from camelCase or PascalCase to snake_case when switching languages or following a new project's style guide.
snake_case vs Other Naming Conventions
get_user_name — all lowercase, underscores between words. Standard in Python, SQL, Ruby, and Rust. Best for readability in most programming contexts.
getUserName — first word lowercase, subsequent words capitalized, no separators. Standard in JavaScript, Java, C#, and most frontend development.
get-user-name — all lowercase, hyphens between words. Standard for URL slugs, CSS class names, HTML attributes, and web file naming.
Frequently Asked Questions
What is snake_case?
snake_case is a naming convention where all letters are lowercase and words are separated by underscores instead of spaces: "get user name" becomes "get_user_name". It is named after the snake-like appearance of the underscores connecting words.
Which programming languages use snake_case?
Python (PEP 8 style guide), Ruby, Rust, PHP, C, and SQL all use snake_case as their standard naming convention for variables, functions, and database columns.
Can it convert camelCase and PascalCase to snake_case?
Yes — the converter handles camelCase, PascalCase, spaces, hyphens, and any mixed format. It detects word boundaries in camelCase by identifying uppercase letters, then converts everything to lowercase joined with underscores.
What is the difference between snake_case and kebab-case?
snake_case uses underscores (get_user_name) and is used in programming languages. kebab-case uses hyphens (get-user-name) and is used for URL slugs and CSS class names. Neither is better — it depends on the language or system.
What is SCREAMING_SNAKE_CASE?
SCREAMING_SNAKE_CASE (also called CONSTANT_CASE) is snake_case with all letters uppercase: GET_USER_NAME. It is used for constants and environment variables in Python (MAX_RETRIES), JavaScript (API_KEY), and Java.
Does it handle special characters?
Yes — special characters, punctuation, and symbols are removed. Numbers are preserved in place. The output contains only lowercase letters, underscores, and numbers.
Is my text private?
Yes. All conversion happens in your browser using JavaScript. Your text is never sent to any server, never stored, and never shared.
Is there a character limit?
No. Paste any length of text and the converter handles everything instantly in your browser.
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