How to find the dimensions of a step file model

Hi, I’ve never messed with anything related to 3D printing before. I’m interested in getting some custom parts printed through a service; I think I’ve found step files of the parts I need through github, but I’m not certain if they’re the right size. Basically, there are different variations of what I need that come in a variety of sizes, but they all have to fit with a specific connector, so the size is not arbitrary (the part cannot be scaled). I’ve searched for many hours trying to figure out how to determine what size the model in my step file is intended to be once printed. I’ve tried online step viewers that claim to provide measurements with no success, and I’ve attempted to use the NIST STEP File Analyzer and Viewer, but it’s extremely technical and not intuitive at all. I have no interest in purchasing 3D modeling software as I do not have the ability to print anything myself. Hopefully, there’s a simple solution that I just haven’t found yet. I would greatly appreciate any assistance anyone can offer!