---
id: glicko2
version: "2.1.0"
license: unclear
license_treatment: permissive
maintenance: aging
---

# glicko2 — Python implementation of glicko2

License: permissive · Maintenance: aging · Downloads: 155.5K/mo

## What it is and what it does

Glicko2 is a Python implementation of the Glicko-2 rating system, a mathematical framework for estimating player skill in competitive environments. It extends simpler rating systems by incorporating rating deviation (uncertainty) and rating volatility, allowing more nuanced ranking updates that account for confidence in each player's true skill level.

The package is a pure-Python library with no runtime dependencies, making it lightweight and easy to integrate into game servers, tournament platforms, or any system that needs to track and update player ratings. It's typically used to compute new ratings after matches or competitions, given prior ratings, rating deviations, and match outcomes.

Use it for:

- Rank players in online multiplayer games or esports tournaments using a mathematically principled algorithm
- Estimate player skill uncertainty to improve matchmaking in competitive systems
- Implement a rating system for board games, chess, or turn-based competitions
- Track skill progression over time in educational or training contexts where performance varies
- Build a leaderboard backend that accounts for win/loss records and rating confidence

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Implements the Glicko-2 rating system, a skill-rating algorithm for ranking players in competitive games based on wins, losses, and rating volatility.

Yes, if you need a Glicko-2 implementation. The package is stable, dependency-free, and carries no security vulnerabilities. The aging maintenance status is not a blocker for a mature algorithm—Glicko-2 itself is a well-established mathematical standard—but verify the API meets your needs before production use.

## Install

pip install glicko2
uv add glicko2
poetry add glicko2

## Installing glicko2

Before you install: Installs with no dependencies and supports Python 3.7 and later. The package is aging—last release was 2024-01-18—but remains stable with no known vulnerabilities.

License in practice: Licensed under MIT (permissive), so you can use, modify, and distribute it freely with minimal restrictions.

Quickstart:

pip install glicko2

from glicko2 import Glicko2

rating_system = Glicko2()
# Compute updated rating after a match outcome

Verify before relying:

- Whether the package is actively maintained or in maintenance-only mode despite aging status
- API stability guarantees or backward-compatibility commitments across versions
- Performance characteristics for large-scale rating updates

## Package facts

- License: not declared (permissive)
- Python support: supports_current
- Install friction: low
- Maintenance: aging
- Downloads: 155.5K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

glicko2 rating system, player skill rating algorithm, competitive ranking system, rating volatility estimation, game player ranking, bayesian rating calculation, tournament rating system, rating-system, game-ranking, competitive-scoring

[View on SkillFed](https://skillfed.io/packages/glicko2) · [View on PyPI](https://pypi.org/project/glicko2/)