Overview

RDFox is an in-memory RDF graph store for teams building knowledge-graph applications that need SPARQL queries and rule-based inference in one system. It is a strong fit when derived knowledge must keep pace with changing data; commercial licensing on request makes cost an important early check.

Key features

RDFox combines RDF storage and SPARQL 1.1 with Datalog rules and ontological reasoning using OWL 2 and SWRL. It also supports OWL 2 RL and SHACL. That combination suits applications that need to infer relationships or work with graph constraints, not just store and retrieve triples.

Incremental reasoning is its clearest differentiator: RDFox updates rule consequences as data changes and can process 2–3 million new-fact inferences per second. This is relevant to systems where new facts should quickly affect the knowledge model, though the stated rate is not a guarantee for every graph or ruleset.

Java applications can use its native API, while a RESTful API supports operating RDFox as a standalone server. Import and export formats include CSV, JSON, N-Triples, Turtle, TriG and OWL 2 Functional-Style Syntax. Multiple servers can replicate knowledge and data changes, supporting continuity during an outage.

Deployment spans cloud, on-premises, on-device and edge environments. Security features include encryption at rest and mutual-TLS client-certificate authentication for endpoint and remote-shell requests; OpenID Connect single sign-on supports external identity systems such as Microsoft Entra. Official Docker images are designed to run without superuser capabilities.

Pricing

The RDFox free evaluation license costs 0.00 USD per free and lasts 30 days. It is limited to evaluation and non-commercial use, so it is not a continuing free tier for production. The RDFox commercial license requires a license key and custom pricing through Oxford Semantic Technologies; teams should establish the quote and licensing fit before committing.

Platforms

RDFox runs on Linux, macOS and Windows, with API, web and self-hosted options. Its deployment range also includes cloud, on-premises, on-device and edge settings, giving infrastructure teams flexibility in where to run a graph service.

Who it's for

RDFox is best suited to organizations building semantic applications that need standards-based RDF querying, ontological reasoning and rapid updates to inferred knowledge. Its APIs, replication and deployment choices also make it relevant to teams integrating a graph store into applications or operating it across varied environments. It is less suitable for buyers who need predictable public commercial pricing or a free license for ongoing commercial use.

Pros and cons

Pros

Real-time incremental inference: changing data can update rule consequences without waiting for a full reasoning pass.
Broad standards and formats: SPARQL 1.1, Datalog, OWL 2 RL, SWRL and SHACL support established knowledge-graph workflows.
Operational flexibility: multiple operating systems, deployment environments, APIs and server replication accommodate varied architectures.
Security options: encryption at rest, mutual TLS and OpenID Connect address important deployment needs.

Cons

Commercial price requires a quote: buyers cannot assess license cost from a published price.
Free access is narrowly scoped: the 30-day evaluation license is non-commercial, so production teams need a commercial license.
Inference throughput is workload-dependent: the stated rate does not establish performance for a particular dataset and ruleset.

Alternatives

Choose Tentris if its free Community option fits: it provides a single-core license, in-memory storage, community support, SPARQL 1.1 and RDF 1.1 support, and transactions. Consider Fluree DB for its free open-source option, with native JSON-LD and SPARQL and local or self-hosted use. GraphDB has a free tier with one parallel query and five repositories, which may suit smaller deployments prepared to work within those limits.

QLever is a free option under the Apache 2.0 license. Apache Jena Fuseki may suit teams seeking a free, self-hosted server under Apache License 2.0. Stardog offers a free license renewable annually, capped at one million stored edges and three databases, without high availability. Virtuoso Universal Server offers one-time Personal and Developer plans. Parliament is a free BSD 3-Clause open-source option.

Browse more options in RDF Databases and Knowledge Graph Software.

Verdict

Choose RDFox for knowledge-graph applications where fast incremental reasoning, standards support and deployment flexibility matter. Its combination of RDF storage, SPARQL and live rule updates is the main reason to choose it; look elsewhere if you need transparent commercial pricing or an ongoing free commercial plan.

	RDFox	RedStore
Free plan	Yes	Yes
Free trial	Yes	No
Paid from	Free	Free
Open source	No	No
Platforms	api, Linux, macOS, self-hosted, Web, Windows	api, Linux, macOS, self-hosted
Free plan	No	Yes
Deployment options	—	self-hosted
SPARQL support	—	sparql 1.1
Supported RDF formats	—	Turtle

RDFox vs RedStore

RDFox

RedStore