#131 · Programming Languages Developer Tool

Python Formatter

Format Python code in your browser by normalizing indentation, operator spacing, blank lines, line endings, and trailing whitespace. The formatter preserves strings and comments, requires no installation, and keeps code on your device.

Developer Input

Source code
lines
Ad space

How to use this developer tool

  1. Paste Python code or upload it as plain text.
  2. Choose an indentation style and maximum consecutive blank lines.
  3. Select the cleanup rules to apply.
  4. Click Format Python or press Ctrl + Enter.
  5. Review, copy, or download the formatted .py output.

What this developer tool does

It performs deterministic whitespace and indentation cleanup without executing the code. Strings, comments, and triple-quoted blocks are protected before spacing rules run.

Protect literals → normalize line endings → calculate indentation → clean operators and commas → limit blank lines → compare output.

This is a browser-based formatting heuristic, not an AST-based replacement for Black or autopep8.

Example

Input

def add(a,b):
 print(a+b)

Output

def add(a, b):
    print(a + b)

Tips for better output

  • Use four spaces for conventional Python indentation.
  • Check the diff before replacing production code.
  • Run Python or an IDE formatter for authoritative syntax-aware formatting.

FAQ

How do I format Python code online without installing Black?

Paste the code, choose four-space indentation, and run the formatter. It cleans common whitespace issues locally in your browser.

How can I convert tabs to four spaces in Python?

Select 4 Spaces and format the code. Leading tab indentation is converted into four-space levels.

Why does Python show mixed tabs and spaces errors?

Python treats tabs and spaces as different indentation tokens. Mixing them can produce inconsistent block levels.

How do I remove trailing whitespace from Python code?

Keep Remove trailing whitespace enabled and run the formatter.

Can this formatter make Python code fully PEP 8 compliant?

No. It handles common formatting rules but does not perform complete AST-based PEP 8 formatting.

Formatting report

AnalysisFormatting heuristic
Protected regionsStrings and comments
Output.py
ExecutionCode is not executed

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