IRIS Research Unit

WSML 2 Reasoner Framework

Reasoners by Language


    The OWL 2 Web Ontology Language, informally OWL 2, is an ontology language for the Semantic Web with formally defined meaning. OWL 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents.

    Elly Reasoner

    Elly logo

    Elly is a Reasoner for ELP knowledge bases, which has been presented as a useful hybrid between both logic programming and description logics that combines EL++ with DLP in a novel way and captures the semantics of the OWL 2 profiles RL and EL. Due to the integration of the OWL API , ELLY can be used as reasoner for the OWL 2 profiles EL and RL. ELLY already passes all (but one) OWL 2 EL conformance tests, see OWL Test Suite Status

  • Website:
  • Source code:
  • Underlying reasoner: IRIS Reasoner (see description in the "Tools" section below)
  • External resources related to OWL 2:

  • OWL 2 Syntax Specification:
  • OWL 2 Profiles Specification:
  • OWL 2 API:



    The RDFS Reasoner translates ontology descriptions in RDFS to predicates and rules. It is using IRIS as an underlying reasoning engine and currently supports the simple, RDF, RDFS and extensional RDFS (eRDFS) entailment regimes. The implementation is based on the work described in [de Bruijn et al. 2007].

    RDFS Reasoner:

  • Online demo:
  • External resources related to OWL 2:

  • RDFS Specification:





    IRIS Reasoner logo

    IRIS - Integrated Rule Inference System is an extensible reasoning engine for expressive rule-based languages. IRIS supports the safe or un-safe Datalog with (locally) stratified or well-founded 'negation as failure'. There is also support for function symbols, equality in rule heads and a comprehensive set of built-in datatypes, predicates and functions.

  • Website:


RDF(S) to WSML Translator


    Implementation work has been supported by the following projects.

    DIP logo Super logo SOA4All logo LarKC logo
Last update: 10-18-2010