Best Knowledge Graph Software in 2026
Updated
In short: RDFox is ranked #1 of 33 as of 5 October 2026, ahead of AllegroGraph and Eclipse RDF4J. The best-ranked option with a free plan is AllegroGraph. The lowest first paid tier on this page is TypeDB at $0.07/mo.
Knowledge graph software supports work with connected data, from modeling relationships to querying them. Compare ontology modeling, graph visualization and import formats, then consider deployment options and the listed query languages. RDF/SPARQL support and semantic reasoning can help distinguish the approaches shown. RDFox, AllegroGraph and Eclipse RDF4J are among the options to examine. Free-plan availability and paid-from pricing offer cost context. Consider the formats and modeling capabilities relevant to your data, as well as the ways you need to query or reason over its connections.
33 knowledge graph software ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
16 of the 25 here have a free tier you can use, 0 have open-source code on record, and 0 have full bars: free, open, on most of your devices and documented.
| # | App | Signal | Free tier | Open code | Devices | From | Score |
|---|---|---|---|---|---|---|---|
| 1 | RDFoxWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | Free | 6.7 | |
| 2 | AllegroGraphWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | Free | 6.6 | |
| 3 | Eclipse RDF4JWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | Free | 6.6 | |
| 4 | GraphDBWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | Free | 6.6 | |
| 5 | ProtégéWeb · Windows · Mac · Linux | Three bars | — | 4 of 6 | Free | 6.6 | |
| 6 | QLeverWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | Free | 6.6 | |
| 7 | RDF StudioWeb · Windows · Mac · Linux · API | Three bars | — | 4 of 6 | Free | 6.6 | |
| 8 | StardogWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | Free | 6.6 | |
| 9 | TypeDBWeb · Windows · Mac · Linux · Self-hosted · API | Three bars | — | 4 of 6 | $0.07/mo | 6.6 | |
| 10 | Apache Jena FusekiWeb · Windows · Linux · Self-hosted · API | Three bars | — | 3 of 6 | Free | 6.5 | |
| 11 | LinkedDataHubWeb · Linux · Self-hosted · API | Two bars | — | 2 of 6 | Free | 6.5 | |
| 12 | TerminusDBWeb · Linux · Self-hosted · API | Two bars | — | 2 of 6 | Free | 6.5 | |
| 13 | HASHWeb · Self-hosted · API · Extension | Two bars | — | 1 of 6 | $1.67/mo | 6.4 | |
| 14 | Neo4jSelf-hosted | Two bars | — | 0 of 6 | $65/mo | 6.4 | |
| 15 | MendixNo platforms listed | Two bars | — | 0 of 6 | Free | 6.3 | |
| 16 | OWLGrEdWeb · Windows | One bar | — | 2 of 6 | Free | 6.3 | |
| 17 | Virtuoso Universal ServerWeb · Windows · Mac · Linux · Self-hosted · API | Two bars | — | — | 4 of 6 | — | 5.6 |
| 18 | OntopWindows · Mac · Linux | One bar | — | — | 3 of 6 | — | 5.4 |
| 19 | PoolParty Semantic SuiteWeb | One bar | — | — | 1 of 6 | — | 5.3 |
| 20 | d.APNo platforms listed | One bar | — | — | 0 of 6 | — | 5.2 |
| 21 | Fluent EditorWindows | No signal | — | — | 1 of 6 | — | 5.2 |
| 22 | MondecaWeb | One bar | — | — | 1 of 6 | — | 5.2 |
| 23 | OxigraphWeb | No signal | — | — | 1 of 6 | — | 5.2 |
| 24 | Progress SemaphoreWeb · Windows · Linux · Self-hosted · API | Two bars | — | — | 3 of 6 | — | 5.2 |
| 25 | Qlevia Enterprise RDF Graph PlatformWeb | No signal | — | — | 1 of 6 | — | 5.2 |
Compare all 25 in a table
| # | App | Score | Free plan | From | Free plan | Paid from | Ontology modeling | Semantic reasoning |
|---|---|---|---|---|---|---|---|---|
| 1 | RDFox | 6.7 | Free plan | Free | No | — | Yes | Yes |
| 2 | AllegroGraph | 6.6 | Free plan | Free | Yes | — | Yes | Yes |
| 3 | Eclipse RDF4J | 6.6 | Free plan | Free | — | — | — | — |
| 4 | GraphDB | 6.6 | Free plan | Free | Yes | — | Yes | Yes |
| 5 | Protégé | 6.6 | Free plan | Free | Yes | — | Yes | Yes |
| 6 | QLever | 6.6 | Free plan | Free | — | — | — | — |
| 7 | RDF Studio | 6.6 | Free plan | Free | Yes | — | Yes | Yes |
| 8 | Stardog | 6.6 | Free plan | Free | Yes | — | — | — |
| 9 | TypeDB | 6.6 | Free plan | $0.07/mo | Yes | — | — | — |
| 10 | Apache Jena Fuseki | 6.5 | Free plan | Free | — | — | — | — |
| 11 | LinkedDataHub | 6.5 | Free plan | Free | Yes | — | Yes | — |
| 12 | TerminusDB | 6.5 | Free plan | Free | Yes | — | Yes | Yes |
| 13 | HASH | 6.4 | Free plan | $1.67/mo | Yes | 20 /mo | Yes | Yes |
| 14 | Neo4j | 6.4 | Free plan | $65/mo | Yes | 65 /mo | — | — |
| 15 | Mendix | 6.3 | Free plan | Free | Yes | — | — | — |
| 16 | OWLGrEd | 6.3 | Free plan | Free | Yes | — | Yes | — |
| 17 | Virtuoso Universal Server | 5.6 | No | — | — | — | — | — |
| 18 | Ontop | 5.4 | No | — | — | — | Yes | Yes |
| 19 | PoolParty Semantic Suite | 5.3 | No | — | — | — | Yes | Yes |
| 20 | d.AP | 5.2 | No | — | — | — | Yes | Yes |
| 21 | Fluent Editor | 5.2 | No | — | Yes | — | Yes | Yes |
| 22 | Mondeca | 5.2 | No | — | — | — | Yes | Yes |
| 23 | Oxigraph | 5.2 | No | — | — | — | — | — |
| 24 | Progress Semaphore | 5.2 | No | — | No | — | Yes | Yes |
| 25 | Qlevia Enterprise RDF Graph Platform | 5.2 | No | — | — | — | — | Yes |
Is your app on this list?
Numbered spots on this list can be sponsored, and a sponsored row is labelled as paid.
Questions about this list
Which knowledge graph software is ranked first on Freedom251?
RDFox is ranked #1 of 33 with a score of 6.7. AllegroGraph is second and Eclipse RDF4J third.
How many of these have a free plan?
16 of the 25 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, TypeDB has the lowest first paid tier we found: $0.07/mo.
How is this list ranked?
Ranked free-and-open first: a usable free tier and open-source code, then the platforms it runs on and its documentation.