Nowadays there is a significant number of codes that allow to do probabilistic seismic hazard assessments.
For instance, the codes that are being evaluated from 2014 are the following:
CRISIS2015 (developer: M.G. Ordaz)
FRISK88M Version 2.0 (developer: G. Toro)
EZ-FRISK (developer: R. McGuire)
XDC52, HAZ50, TREE50 (developer: B. Youngs)
HazFX v3.f, hazgridX v3.f, filtrate.peer.f (developers: A. Frankel and S. Harmsen)
ALEAS (developer: J. Savy Abramowitz)
EQ-Elements (developer: A. Mendez)
GP-Haz (developer: P. Tan)
NEWHAZ (developer: M. Stirling)
mrs 3.1 (developer: R. LaForge)
OpenSHA (developer: N. Field)
HAZDIR (developer: B. Rowshandel