Python Formatter
Format Python code automatically with PEP 8 compliance, ensuring consistent 4-space indentation, 79-character line limits, and proper whitespace around operators. Instantly beautifies Python scripts with correct import ordering, function spacing, and snake_case naming validation. Handles Python 2.7 through 3.12 syntax including f-strings, type hints, and async/await patterns without server uploads.
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Issue Description
Hint: Paste any code and click Format to beautify indentation, spacing, and structure instantly.
How It Works
- Step 1: Paste your Python code with any formatting issues—mixed indentation, inconsistent spacing, or PEP 8 violations.
- Step 2: The formatter parses your code using AST (Abstract Syntax Tree) analysis to understand structure while preserving logic and comments.
- Step 3: Applies PEP 8 style guide rules including 4-space indentation, 79-character line wrapping, two blank lines between functions, and proper spacing around operators (x = y + z).
- Step 4: Returns beautifully formatted Python code that passes flake8 and pylint checks, ready for code reviews and production deployment.
Unformatted vs Formatted Python
| Feature | Unformatted Python | PEP 8 Formatted |
|---|---|---|
| Indentation | Inconsistent tabs/spaces | 4 spaces (PEP 8) |
| Line Length | Unlimited, hard to read | 79 characters max |
| Spacing | Random whitespace | Consistent operators/commas |
| Imports | Mixed order | Sorted, grouped by type |
| Naming | camelCase, mixed styles | snake_case (PEP 8) |
Python Formatting Examples
Example 1: Basic Formatting and Spacing
def calculate(x,y,z):
result=x+y*z
if result>100:
return result
else:
return 0
class MyClass:
def __init__(self,value):
self.value=value
def getValue(self):
return self.valuedef calculate(x, y, z):
result = x + y * z
if result > 100:
return result
else:
return 0
class MyClass:
def __init__(self, value):
self.value = value
def get_value(self):
return self.valueKey Changes:
The formatter applies PEP 8 spacing rules: spaces after commas in function parameters (x, y, z), spaces around operators (x + y * z), and spaces around comparison operators (result > 100). Indentation is standardized to 4 spaces throughout, replacing any tabs or inconsistent spacing. Two blank lines separate the function from the class definition, following PEP 8's top-level definition spacing. Method names are converted from camelCase (getValue) to snake_case (get_value) per Python naming conventions. The __init__ method gains proper spacing, and a blank line separates methods within the class for readability. This formatting ensures the code passes automated style checkers like flake8 and is immediately readable by Python developers following community standards.
Example 2: Import Sorting and Line Length
from mypackage import function1,function2,function3,function4,function5,function6,function7
import sys,os
from datetime import datetime
import numpy as np
def very_long_function_name_that_exceeds_line_length(parameter1,parameter2,parameter3,parameter4):
return parameter1+parameter2+parameter3+parameter4import os
import sys
from datetime import datetime
import numpy as np
from mypackage import (
function1,
function2,
function3,
function4,
function5,
function6,
function7,
)
def very_long_function_name_that_exceeds_line_length(
parameter1, parameter2, parameter3, parameter4
):
return parameter1 + parameter2 + parameter3 + parameter4Key Changes:
The formatter reorganizes imports following PEP 8 import order: standard library (os, sys), then third-party packages (numpy), then local imports (mypackage), with blank lines separating groups. Long import statements are split across multiple lines with trailing commas for easier git diffs. The function definition exceeding 79 characters is wrapped across lines with parameters indented to align visually. The return statement gains proper spacing around operators. Import sorting prevents merge conflicts and makes dependencies immediately visible. Line length enforcement (79 characters) ensures code readability on standard terminal widths and during code reviews. The trailing comma style in imports allows adding new imports without modifying existing lines, improving version control history. This formatting is essential for team projects and open-source contributions where PEP 8 compliance is expected.
Frequently Asked Questions
Can I configure line length or toggle between Black and PEP 8 styles?
The formatter applies PEP 8 (79-character lines) by default. Black-style formatting (88-character lines, aggressive reformatting) requires post-processing or using Black directly. Custom configurations (2-space indent, alternate quote styles) are not supported. The tool prioritizes PEP 8 compliance.
Is my Python code sent to external servers during formatting?
No. All AST parsing and reformatting run client-side via JavaScript-based Python parsers. Your Python source—whether proprietary ML algorithms, confidential business logic, or internal libraries—stays in your browser. Zero network transmission occurs.
What Python syntax is unsupported or problematic?
The formatter handles Python 2.7 through Python 3.12 syntax. Files mixing code with large multiline strings (SQL queries, embedded HTML) may format unpredictably. Unusual indentation (tabs mixed with spaces) triggers errors—use consistent spacing. Files exceeding 5MB hit browser limits.