  We present the program package 2HDECAY for the calculation of the partial
decay widths and branching ratios of the Higgs bosons of a general
CP-conserving 2-Higgs doublet model (2HDM). The tool includes the full
electroweak one-loop corrections to all two-body on-shell Higgs decays in the
2HDM that are not loop-induced. It combines them with the state-of-the-art QCD
corrections that are already implemented in the program HDECAY. For the
renormalization of the electroweak sector an on-shell scheme is implemented for
most of the renormalization parameters. Exceptions are the
soft-$\mathbb{Z}_2$-breaking squared mass scale $m_{12}^2$, where an
$\overline{\text{MS}}$ condition is applied, as well as the 2HDM mixing angles
$\alpha$ and $\beta$, for which several distinct renormalization schemes are
implemented. The tool 2HDECAY can be used for phenomenological analyses of the
branching ratios of Higgs decays in the 2HDM. Furthermore, the separate output
of the electroweak contributions to the tree-level partial decay widths for
several different renormalization schemes allows for an efficient analysis of
the impact of the electroweak corrections and the remaining theoretical error
due to missing higher-order corrections. The latest version of the program
package 2HDECAY can be downloaded from the URL
https://github.com/marcel-krause/2HDECAY .
