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!


2021/06/17: Version 9.3.0 released
deal.II version 9.3.0 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.
2021/6/18: 9th deal.II users and developers workshop
Given that we can't have in-person workshops this year, we will have a 1-day public day with talks discussing what's new in deal.II. For more information, see here.
2021/5/19: New tutorial programs
Over the past year, many new tutorial programs have been merged -- a total of ten, more than for any previous release of deal.II!
Specifically, these are the new programs: step-19 introduces particle methods, and step-68 uses these for tracking locations in a flow field. step-66 is a matrix-free geometric multigrid solver for a nonlinear problem. step-71 and step-72 illustrate automatic and symbolic differentiation. step-77 demonstrates deal.II's SUNDIALS interfaces to solve a nonlinear problem. step-74 shows the SIPG approach to discontinuous Galerkin methods. step-76 is an explicit integrator for the Euler equations. step-78 solves the Black-Scholes equations, and step-79 solves a topology optimization problem.

(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.