# official-stockfish/Stockfish

A free and strong UCI chess engine

Repository: https://github.com/official-stockfish/Stockfish
Canonical: https://ross.abutalabs.com/products/stockfish
Homepage: https://stockfishchess.org/
Language: C++
License: GPL-3.0
License Family: copyleft
Topics: chess, chess-engine, cpp, stockfish, uci
Last push: 2026-08-25T17:28:02+00:00

## Health v2 (maintenance only)
Score: 77/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 36, longevity 100
- inputs: {"age_days": 4459, "days_push": 8, "days_rel": 214, "gap_med": 255.5, "n_releases_24m": 3}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 16419, forks 2992 (observed 2026-08-28T04:11:16.297461+00:00)

## What it is
Stockfish is a free, open-source UCI chess engine that analyzes positions and computes optimal moves using alpha-beta search with NNUE neural network evaluation. It ships without a GUI and is designed to be paired with external chess interfaces.

## Use cases
- analyze chess positions and find the best moves
- power a chess website or app with a strong engine
- run engine-vs-engine matches and testing
- get move-by-move analysis of my games
- embed a chess engine in a GUI like a chessboard app

## When to choose
- you need a top-strength chess engine for analysis or play
- you want a UCI engine compatible with standard chess GUIs
- you need cross-platform support including mobile

## When to avoid
- you want a graphical chessboard out of the box
- you need engines for games other than chess

## Facets
- artifact type: application
- maturity: active
- function: game-engine, machine-learning
- domain: gaming-tools, simulation
- platform: cross-platform, windows, cli
- tags: chess, uci, nnue, chess-engine, linux, macos, android, ios

## Member repositories
- official-stockfish/Stockfish (main) score 77

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:16.297461+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:05:07.115201+00:00, confidence not recorded.
  - readme: https://github.com/official-stockfish/Stockfish (fetched 2026-08-28T04:11:16.297461+00:00, sha 7a44867aba78)
  - homepage: https://stockfishchess.org/ (fetched 2026-08-29T08:02:23.846260+00:00, sha 64c0a64cef30)
  - site_page: https://stockfishchess.org/about (fetched 2026-08-29T08:02:23.855586+00:00, sha f1884253e65e)
- Data as of 2026-08-30T08:39:29.467469+00:00.