RDFox
activeby Oxford Semantic Technologies (Samsung Electronics) · since 2017
In-memory RDF store with incremental Datalog reasoning, now owned by Samsung.
Overview
RDFox is a high-performance, in-memory RDF triple store and Datalog reasoner developed at the University of Oxford and commercialized by Oxford Semantic Technologies, which Samsung Electronics acquired in 2024. Its distinguishing feature is incremental materialization: rules and OWL 2 RL axioms are re-evaluated efficiently as data changes, so queries see up-to-date inferences without full recomputation. It runs as a server or embedded library, including an Android build used on Samsung Galaxy devices. Choose it when rule-based reasoning speed matters more than raw dataset size.
Strengths & trade-offs
Strengths
- +Incremental Datalog and OWL 2 RL reasoning keeps inferences current as data changes
- +Parallel in-memory engine with very fast materialization
- +Runs embedded on edge and mobile devices, including Android
- +Rich rule language with negation, aggregation and stratification
Trade-offs
- −Proprietary with no free production tier
- −RAM-bound dataset size
- −Samsung ownership may steer roadmap toward on-device use
Great for
- +Rule-based decision and compliance engines
- +On-device personal knowledge graphs
- +Real-time knowledge-graph reasoning
- +Product configuration and validation
Think twice for
- −Very large graphs that exceed RAM
- −Property-graph Cypher workloads
- −Open-source-only projects
Capabilities
Native or official first-party support · 4 of 25 tracked
Scale & consistency
- Comfortable data size
- Medium · ≤ 10 TB
- Horizontal scaling
- None
- Multi-region
- No
- Transactions
- Full ACID
- Consistency
- Strong
- Schema
- Schemaless
- Architecture
- In memory, Single node, Embedded, Client server
- Query languages
- SPARQL, Datalog, OWL 2 RL
Data and materialized inferences are held in RAM on one machine; billions of triples need large memory.
Deployment
Ecosystem
Alternatives to RDFox
Standards-compliant RDF triplestore with reasoning, connectors and MCP support for GraphRAG.
rdfox vs ontotext-graphdb →Enterprise knowledge-graph platform: RDF store, reasoning and virtual graphs over your sources.
rdfox vs stardog →Lisp-built RDF and document knowledge graph with vector store, reasoning and LLM agents.
rdfox vs allegrograph →Small, fast SPARQL database in Rust that embeds in Rust, Python and JavaScript or runs as a server.
rdfox vs oxigraph →Apache Jena's native RDF store, embeddable in Java or served over SPARQL with Fuseki.
rdfox vs apache-jena-tdb →Eclipse Foundation's Java RDF framework with native, LMDB and in-memory SPARQL stores.
rdfox vs eclipse-rdf4j →RDFox FAQ
What is RDFox?
RDFox is a RDF / triple store database by Oxford Semantic Technologies (Samsung Electronics), first released in 2017. RDFox is a high-performance, in-memory RDF triple store and Datalog reasoner developed at the University of Oxford and commercialized by Oxford Semantic Technologies, which Samsung Electronics acquired in 2024. Its distinguishing feature is incremental materialization: rules and OWL 2 RL axioms are re-evaluated efficiently as data changes, so queries see up-to-date inferences without full recomputation. It runs as a server or embedded library, including an Android build used on Samsung Galaxy devices. Choose it when rule-based reasoning speed matters more than raw dataset size.
Is RDFox open source?
No. RDFox is proprietary, closed-source software.
Does RDFox support ACID transactions?
Yes. RDFox supports full ACID transactions, with strong consistency.
Does RDFox scale horizontally?
RDFox does not scale horizontally; it runs on a single node, so you scale it up rather than out. It is comfortable at medium scale (≤ 10 TB).
How can I run RDFox?
You can self-host it, embed it in your application and run it at the edge.
What is RDFox best for?
RDFox is a strong fit for rule-based decision and compliance engines; on-device personal knowledge graphs; and real-time knowledge-graph reasoning. Think twice for very large graphs that exceed RAM.
What are the best alternatives to RDFox?
Common alternatives to RDFox include Graphwise GraphDB (Ontotext), Stardog, AllegroGraph, Oxigraph and Apache Jena TDB. The right choice depends on your workload, scale and hosting; WhichDB's smart match ranks them against your requirements.
How popular is RDFox?
RDFox ranks #438 of 844 databases on the WhichDB Score (3.4/100), and #11 among RDF / triple store databases. The score combines public adoption signals such as package downloads, GitHub activity, job posts and developer discussion.