deal.II — an open source finite element library

What it is: A C++ software library supporting the creation of finite element codes and an open community of users and developers. (Learn more.)

Mission: To provide well-documented tools to build finite element codes for a broad variety of PDEs, from laptops to supercomputers.

Vision: To create an open, inclusive, participatory community providing users and developers with a state-of-the-art, comprehensive software library that constitutes the go-to solution for all finite element problems.

deal.II is open source and available for free!
There are many resources for learning deal.II and asking for help.
deal.II is a community project. We welcome all who want to participate!


2018/07/23-27: 6th deal.II users and developers workshop
The 6th deal.II users and developers workshop happens in Trieste, Italy, July 23-27, 2018. For more information, see here and here.
2018/05/11: Version 9.0.0 released
deal.II version 9.0.0 was released today. A full list of changes can be found here and a long description of changes is in the manuscript here. Download links are on the download page, or the release page on github.
2018/05/07: step-60 - non-matching discretizations
The new step-60 example, see here, by Luca Heltai and Giovanni Alzetta shows how to deal with non-matching discretizations defined on different meshes, and how to use distributed Lagrange multipliers for this.
2017/06/17: deal.II is now part of the SPEC CPU 2017 benchmark
A program based on the deal.II library is part of the new industry standard SPEC CPU 2017 benchmark testsuite that is used to determine the speed of computers. It is part of the floating point testsuite as 510.parest.

The inclusion of our software into an industry standard benchmark testsuite will lead to better support of compilers and machines for the kind of program we write, in particular for unstructured hierarchical mesh computations. This will in turn help make our codes run faster on future systems.

(older news)


The primary means of communicating with deal.II developers and users is by email:

The deal.II discussion group is used by developers to announce new features and by users to ask questions about how to do things with deal.II. This is also the forum to post bug reports.

The development of the library is done on the deal.II project using Issues and Pull-Requests.

You can send an email to the project administrators Wolfgang Bangerth, Guido Kanschat, Timo Heister, and Matthias Maier if necessary.

We appreciate comments and suggestions on deal.II. They can be addressed to either of the addresses above, depending on their public or private nature.

Legal Notice: Some countries' laws require us to post this legal notice.