Skip to content


Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

Latest commit

that can be used to work with perpendicular components with respect
to lightcone momenta.

Git stats


Failed to load latest commit information.


license: GPLv3 latest release compatibility

FeynCalc is a Mathematica package for symbolic evaluation of Feynman diagrams and algebraic calculations in quantum field theory and elementary particle physics.

Visit our wiki to learn more about FeynCalc!


You can ask your questions about FeynCalc or participate in the related discussions in our forum powered by GitHub Discussions


FeynCalc manual is still work in progress but is already mature enough to be useful for normal users.

The PDF version of the manual can be found here. If you prefer the web version, please visit this website.

Notice that the current manual applies to the development version of FeynCalc. Hence, it may describe functionality that is not available in the stable version.

The online manual for the current stable version can be found here. It is web-only, i.e. there is no PDF version available.

Using FeynCalc in your research

Development of FeynCalc costs a lot of effort and is done on a largely voluntarily basis. To support the developers and increase their academic visibility, please acknowledge our work when you use FeynCalc in your research. You can do so by citing the following FeynCalc papers:

  • V. Shtabovenko, R. Mertig and F. Orellana, P3H-20-002, TTP19-020, TUM-EFT 130/19, arXiv:2001.04407.

  • V. Shtabovenko, R. Mertig and F. Orellana, "New Developments in FeynCalc 9.0", Comput. Phys. Commun., 207, 432--444, 2016, arXiv:1601.01167.

  • R. Mertig, M. Böhm, and A. Denner, "Feyn Calc - Computer-algebraic calculation of Feynman amplitudes", Comput. Phys. Commun., 64, 345--359, 1991.


FeynCalc is covered by the GNU General Public License 3.

Copyright (C) 1990-2023 Rolf Mertig

Copyright (C) 1997-2023 Frederik Orellana

Copyright (C) 2014-2023 Vladyslav Shtabovenko

FeynCalc is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

FeynCalc is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with FeynCalc. If not, see