yaml2sbml is a small package in Python to convert an ODE model specified in a YAML file into SBML for ODE simulation and into PEtab for parameter fitting. yaml2sbml offers: a translator of ODE models specified in YAML into SBML/PEtab via a Python and a command-line interface; a format validator for the input YAML; and a model editor, which provides a simplified interface to generate, import and export YAML models.