Black

Judgement

What it is

Developer tool

What it does

A Python code formatter with almost no options that rewrites code into one deterministic style.

Adopt it when

A Python team wants formatting settled automatically and is not already using Ruff's compatible formatter.

Watch out

Ruff's formatter produces near-identical output much faster, so many projects now use that instead.

Ready for

Production-ready

Runs as

Command line

Built with

Python

How established

Established: started 8 years ago, latest release 26.10.1.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-06 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Black → CPython → GCC → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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