Universal Code Beautifier

How to use Universal Code Beautifier

1. Paste your code and select the language.
2. Read the formatted output.
3. Copy it back — and set up a real formatter for anything you maintain.
4. Python and YAML are indentation-sensitive: reformatting can change meaning, not just layout.
5. Formatting does not validate — syntax errors remain syntax errors.
6. Code stays in your browser and is not transmitted.

Formatting is a readability tool, not a correctness one

Whitespace changes nothing about what most languages do — with real exceptions. Python indentation is the block structure, so reformatting it can change behaviour rather than appearance. YAML is the same. In brace languages the risk is lower but not zero: JavaScript’s automatic semicolon insertion means joining or splitting lines can alter parsing in a handful of cases. Read the output rather than trusting it, particularly for indentation-sensitive languages.

The argument about style is the point of automating it

Tabs against spaces, brace placement, line length — these have consumed an extraordinary amount of engineering attention over decades, and none of the answers matter. What matters is that a codebase is consistent, so that a diff shows what changed rather than who edited it. That is why the modern answer is an opinionated formatter with almost no options: Prettier, Black, gofmt, rustfmt. Removing the choice removes the argument.

Put it in the pipeline, not in a browser tab

For a project, run the formatter on save and in a pre-commit hook, with the configuration committed. Then formatting never appears in a pull request, every contributor produces identical output, and code review is about the code. A web formatter is for a snippet you are reading once — pasting project code into a browser to reformat it and pasting it back is a workflow that will eventually lose something.