Packed with useful features and components that will help you deploy it in almost any use case. Highlights include:

  • SPARQL 1.0 Support
  • Intuitive/powerful mapping language
  • Support for free and commercial DBMS
  • Compatible with DBMS federation tools
  • Providers for Sesame and OWLAPI
  • Integrated with Protege 4.x
  • SPARQL end-point

Take a look a the in detail description of -ontop-'s components!



The SPARQL engine supports the following entailment regimes out of the box:

With inference you will be able to apply virtual RDF and RDB2RDF /OBDA technology in use cases reserved for traditional OWL reasoners (slow with lots of data) or RDF triples stores based on forward or backward chaining (inefficient reasoning). Interesting use cases for inference in RDB2RDF/OBDA include:

  • On-the-fly Ontology-based Data Access
  • SPARQL over RDFS/OWL mappings
  • Data Integration with DB federation


Extremely high performance, even in the presence of very large data sets, complex queries and large ontologies.

ontop implements the latest generation query rewriting techniques that translate your SPARQL into SQL in the best possible way. The SQL queries are so efficient that they often allow provide 10x times better performance than other SPARQL engines (open source or even commercial), and in complicated queries/data sets, up to 500x times.

Dont't believe us? Take a look at our benchmarks and take it for test drive!