GeLL is a General Likelihood Library for use in phylogenetics. It is intended to provide classes that facilitate investigating new models and techniques. It is not intended for everyday use in phylogenetic studies as it is optimised for easy use of new models rather than speed.

GeLL achieves this versatility by allowing models to be defined using an array of Strings where each string represents an equation. This allows new models to be defined quickly and easily. The driver executable included allows many different models to be run simply by changing the text file defining the model.

Quick Start

A quick start guide is available here and has further information on which downloads you may require if you are uncertain. If you just wish to use the GeLL driver this is definitely the best place to start.

Overview and examples

A more in-depth overview of GeLL, including examples and how to use the provided driver is here. This documentation is also included in the downloads below.


The current version of GeLL is v2.0.

Library Downloads

All packages come with documentation, including full javadoc. Java 1.7 is required.

Examples Downloads

Examples for the use of the driver or using GeLL in code.


As well as being included in the above packages javadoc documentation is also available here.


GeLL is licensed under GPL version 3. Some source code is in the public domain while some example datasets and test cases are under a different license. Please see the documentation that comes with GeLL for full details.


The latest version of the GeLL source code is available on github at

Old Versions

Are avaliable here.