Open Journal Systems is the more common of the two in our index: it runs on 22 websites against 9 for DSpace. Counts come from real scans of each site's home page, not vendor claims, and cover the sites in TechLookup's index rather than the whole web.
DSpace is a software platform for academic, non-profit, and commercial organizations to create and manage open digital repositories.
Open Journal Systems (OJS) is an open-source software application for managing and publishing scholarly journals.
Within the dms sites we have indexed, DSpace holds 17% and Open Journal Systems 42%.
Want to know which one a particular site uses? Look it up and see its whole stack, or compare two sites side by side.