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Head-to-head · Knowledge Graph Software

Progress Semaphore vs OpenLink Virtuoso

  • Updated Oct 2026
  • Both researched from official sources
  • 5 checks side by side
Higher score Progress Semaphore #3 in Knowledge Graph Software 9.0/10 Pricing on request · 30-day trial Free trial✓ 4 of 4 features Visit site
OpenLink Virtuoso #8 in Knowledge Graph Software 8.1/10 Open source · 30-day trial Free trial✓ 0 of 4 features Visit OpenLink

Progress Semaphore leads on 0 checks, OpenLink Virtuoso on 0, and 5 are even. Who comes out ahead on the 5 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scoreProgress Semaphore · 9.0/10
  • Free trialboth
  • Most featuresProgress Semaphore · 4 of 4

Progress Semaphore scores higher on our rubric for knowledge graph software: 9.0 against 8.1 out of 10; our editors rank them #3 and #8.

Progress Semaphore is the better fit for mature ontology and semantic-classification teams. OpenLink Virtuoso is the better fit for mature hybrid SQL and RDF deployments.

  • Progress Semaphore fits best

    Mature ontology and semantic-classification teams

  • OpenLink Virtuoso fits best

    Mature hybrid SQL and RDF deployments

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Side by side

Feature Progress Semaphore 9.0/10 Visit ↗ OpenLink Virtuoso 8.1/10 Visit ↗
At a glance
Editor score 9.0 8.1
Ranking #3 in Knowledge Graph Software #8 in Knowledge Graph Software
Best for Mature ontology and semantic-classification teams Mature hybrid SQL and RDF deployments
Pricing model Paid Free
Starting price — Free
Free plan — Not checked yet
Free trial 30 days 30 days
Free trial length 30 days 30 days
Deployment Cloud, Self-hosted Cloud, Self-hosted
Platforms Web, Windows, Linux Windows, macOS, Linux
Support Community, Docs Tickets, Community, Docs
Compliance SOC 2 GDPR
Integrations 7 integrations 8 integrations
Built for Mid-market, Enterprise Small business, Mid-market, Enterprise
Features Progress Semaphore 4/4 · OpenLink Virtuoso 0/4
Ontology modeling ✓ (best) Not checked yet
Semantic reasoning ✓ (best) Not checked yet
RDF/SPARQL support ✓ (best) Not checked yet
Graph visualization ✓ (best) Not checked yet
Specs
Import formats RDF, Excel spreadsheets Not checked yet
Deployment Both Both
Query languages SPARQL Not checked yet
Our review
Pros
  • Covers ontology, taxonomy, thesaurus, RDF, and SPARQL workflows
  • Adds classification, fact extraction, enrichment, visualization, and mapping
  • Supports web, Windows, Linux, APIs, and cloud, on-premises, or hybrid deployment
  • Combines SQL, RDF quad storage, SPARQL, and relational RDF views
  • Supports replication, clustering, virtualization, and web-service deployment
  • Connects through ODBC, JDBC, ADO.NET, OLE-DB, GraphQL, and HTTP
Cons
  • Contact-sales pricing makes plan comparison less immediate
  • Its enterprise focus may exceed the needs of smaller teams
  • Development is limited to demos, development, and capability evaluations
  • Its broad scope may exceed the needs of narrow graph-only projects
  • Enterprise capabilities use custom licensing terms
  • Advanced deployments require database and data-integration expertise
Our verdict

Progress Semaphore is a semantic AI platform for enterprises managing knowledge models, ontologies, taxonomies, controlled vocabularies, thesauri, and metadata. It is suited to teams building enterprise knowledge graphs, semantic search,…

Read the review →

OpenLink Virtuoso is a cross-platform multi-model database and data integration platform for organizations working with relational, RDF, graph, XML, and federated data. It combines a relational SQL engine with native RDF quad storage,…

Read the review →
  1. Progress SemaphoreKnowledge Graph Software 9.0Pricing on request · 30-day trial
  2. OpenLink VirtuosoKnowledge Graph Software 8.1Open source · 30-day trial

Strengths and trade-offs

  • Progress Semaphore — where it wins

    • Covers ontology, taxonomy, thesaurus, RDF, and SPARQL workflows
    • Adds classification, fact extraction, enrichment, visualization, and mapping
    • Supports web, Windows, Linux, APIs, and cloud, on-premises, or hybrid deployment

    Where it doesn't

    • Contact-sales pricing makes plan comparison less immediate
    • Its enterprise focus may exceed the needs of smaller teams
    • Development is limited to demos, development, and capability evaluations

  • OpenLink Virtuoso — where it wins

    • Combines SQL, RDF quad storage, SPARQL, and relational RDF views
    • Supports replication, clustering, virtualization, and web-service deployment
    • Connects through ODBC, JDBC, ADO.NET, OLE-DB, GraphQL, and HTTP

    Where it doesn't

    • Its broad scope may exceed the needs of narrow graph-only projects
    • Enterprise capabilities use custom licensing terms
    • Advanced deployments require database and data-integration expertise
  • Progress Semaphore9.0/10 · Pricing on request · 30-day trial

    A mature platform for ontology management, semantic enrichment, and enterprise knowledge graphs.

    Visit siteFull verdict →
  • OpenLink Virtuoso8.1/10 · Open source · 30-day trial

    A broad open-source platform for teams combining relational and RDF workloads.

    Visit OpenLinkFull verdict →

More comparisons

All knowledge graph software comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update