Python Linter
Python Linter is a browser-based code quality tool that checks your Python scripts for PEP 8 violations, syntax errors, naming convention issues, and structural complexity. Five integrated modes share a single workspace: a full PEP 8 linter that flags whitespace, spacing, and convention issues; a formatter that auto-corrects indentation, trailing whitespace, and semicolons; a syntax checker that catches mismatched brackets and missing colons; a style checker that enforces snake_case naming and Pythonic patterns; and a code analyzer that calculates complexity metrics and identifies unused imports. Paste your code, type it directly, or upload .py files from your computer. The Dracula theme keeps the editor comfortable during long sessions, and the status bar tracks cursor position, line count, and file size in real time. Everything runs locally in your browser, so your code never leaves your device.
Python Linter
Scans for PEP 8 violations including line length, whitespace, operator spacing, naming, bare excepts, and more.
Python Formatter
Auto-formats code with 4-space indentation, comma spacing, trailing whitespace removal, and blank line normalization.
Syntax Checker
Validates bracket matching, string closure, colon placement, and indentation consistency across your code.
Style Checker
Enforces snake_case for functions, CapWords for classes, and flags deprecated patterns like has_key() and len() comparisons.
Code Analyzer
Reports line metrics, cyclomatic complexity, unused imports, and functions exceeding 20 lines for refactoring guidance.
Online Python Linter with PEP 8 Checking
Built on CodeMirror with Python syntax highlighting and the Dracula color scheme, the editor provides syntax-aware coloring for keywords, strings, numbers, decorators, and comments. You'll see paired parentheses, brackets, and braces light up as you navigate. Use code folding to collapse function bodies or class definitions and focus on exactly what you're working on. The tool scans for over 15 PEP 8 rules, including line length (E501), tabs (W191), operator spacing (E225), and naming conventions (C0103). Results show up instantly in a panel below the editor, complete with line numbers, rule codes, and helpful explanations.
Upload Python Files Directly
You can bring in existing scripts by clicking the Upload button or dragging files directly onto the editor. The tool supports .py, .pyw, .pyi, and plain text files, loading your content instantly for linting or formatting. Since there are no artificial file size limits, you can easily work with production-scale modules.
Format Python Code with One Click
Switch to the Format tool to clean up your code instantly. It converts tabs to 4-space indentation, removes trailing whitespace, fixes comma spacing, and collapses excessive blank lines to PEP 8 standards. Your formatted code stays right in the editor so you can keep working or download the result.
Syntax Validation, Style Enforcement, and Code Analysis
You can switch between linting, syntax checking, and code metrics with a single click. Your code remains in the workspace as you move between tools, letting you lint a file, review the structure, and analyze complexity in one seamless workflow. The syntax checker identifies mismatched brackets, unclosed strings, or missing colons at a glance. Meanwhile, the style checker helps you stick to Pythonic patterns, enforcing snake_case for functions and CapWords for classes while flagging deprecated methods like has_key(). It even alerts you to unnecessary .keys() iterations or comparisons that should use truthiness instead.
Cyclomatic Complexity and Code Metrics
The code analyzer gives you a deep dive into your script's structure across eight key metrics, from line counts to cyclomatic complexity. If a complexity score hits 15 or higher, it turns red to signal that your code might need some refactoring. You can also spot potentially unused imports and functions that run longer than 20 lines, helping you keep your project clean and maintainable.
Download or Copy Your Linted Code
Save your work as a .py file using the Download button, or grab the entire editor content with the Copy button for pasting into terminals, IDEs, or version control. Both options remain accessible at all times, regardless of which mode is active.
Free Python Linter for Developers and Students
This tool delivers a complete Python code quality toolkit for anyone writing scripts, building applications, or learning Python for the first time. There is nothing to install and no account to create: every feature from PEP 8 linting and code folding to complexity analysis is ready to use right away. Exports come clean, without watermarks or branding. Because all processing takes place locally in your browser, proprietary code, API keys, and sensitive logic stay completely private and never travel across the network.
No Signup, No Limits, No Data Collection
Every mode, file upload, download, and analysis is available the moment you open the page. There are no premium tiers, usage caps, or restrictions on file size waiting behind a paywall. Your session data is wiped clean the instant you close the browser tab.
Client-Side Processing for Complete Privacy
Privacy is built into every step because your code analysis happens entirely inside your browser. Since your files and snippets never touch a remote server, you can safely handle proprietary business logic, authentication scripts, and confidential project files without worrying about data leaks.
Related Python and Developer Tools
These tools complement your Python code quality workflow:
- Python Formatter -- auto-format Python code with PEP 8 compliant indentation and spacing
- Python Syntax Checker -- validate bracket matching, string closure, and colon placement
- Python Style Checker -- enforce naming conventions and Pythonic patterns
- Python Code Analyzer -- measure complexity, detect unused imports, and flag long functions
- JavaScript Editor -- write, format, minify, and validate JavaScript code
- JSON Formatter -- format and validate JSON data structures
- HTML Editor -- write and edit HTML with syntax highlighting
- CSS Linter -- check CSS for syntax errors and best practice violations