Python Variable Naming – snake_case & PEP 8 Guide

Published 2026-04-14 · convertcase.in

Python has official style guidelines (PEP 8) that specify exactly how to name variables, functions, classes, and constants. Here's a complete reference.

Try it now — free instant conversion

No signup · No limits · Works on all devices

Open ConvertCase →

1Variables and Functions

snake_case: user_name, get_user_profile, calculate_total_price

2Classes

PascalCase: UserProfile, OrderItem, DataProcessor

3Constants

SCREAMING_SNAKE_CASE: MAX_RETRY_COUNT, DEFAULT_TIMEOUT, API_BASE_URL

4Modules/Files

snake_case: data_processor.py, user_models.py, api_utils.py

5Private vs Public

Single underscore prefix for internal: _private_method. Double underscore for name mangling: __very_private.

Frequently Asked Questions

Can I use camelCase in Python?

You can, but PEP 8 (the official style guide) recommends against it for functions and variables. Use camelCase only when inheriting an API that already uses it.