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Head-to-head · Knowledge Graph Software

Progress Semaphore vs Stardog

  • 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
Stardog #5 in Knowledge Graph Software 8.8/10 Free plan Free plan✓ 0 of 4 features Visit Stardog

Progress Semaphore leads on 0 checks, Stardog on 1, and 4 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 planonly Stardog
  • Free trialonly Progress Semaphore
  • Most featuresProgress Semaphore · 4 of 4

Progress Semaphore scores higher on our rubric for knowledge graph software: 9.0 against 8.8 out of 10; our editors rank them #3 and #5.

Stardog offers free plan; Progress Semaphore doesn't.

Progress Semaphore is the better fit for mature ontology and semantic-classification teams. Stardog is the better fit for federated knowledge graphs across enterprise data.

  • Progress Semaphore fits best

    Mature ontology and semantic-classification teams

  • Stardog fits best

    Federated knowledge graphs across enterprise data

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 ↗ Stardog 8.8/10 Visit ↗
At a glance
Editor score 9.0 8.8
Ranking #3 in Knowledge Graph Software #5 in Knowledge Graph Software
Best for Mature ontology and semantic-classification teams Federated knowledge graphs across enterprise data
Pricing model Paid Free plan + paid
Starting price — —
Free plan — ✓ (best)
Free trial 30 days —
Deployment Cloud, Self-hosted Cloud, Self-hosted
Platforms Web, Windows, Linux Web
Support Community, Docs Community, Docs · 24/7
Compliance SOC 2 SOC 2
Integrations 7 integrations 20 integrations
Built for Mid-market, Enterprise Mid-market, Enterprise
Features Progress Semaphore 4/4 · Stardog 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 Not checked yet
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
  • Queries remote data through virtual graphs without necessarily moving it
  • Supports SPARQL, SQL, GraphQL, REST, inference, and ontology management
  • Offers both managed cloud and self-managed enterprise deployment
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
  • The Free plan is limited to 1 million stored edges
  • Enterprise pricing requires contacting sales
  • It is proprietary rather than open source
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 →

Stardog is a knowledge-graph and semantic AI platform for enterprises that need to connect and query distributed data. Its virtual graphs and connectors work with relational, NoSQL, file, cloud, and SPARQL sources, while SPARQL, SQL-based…

Read the review →
  1. Progress SemaphoreKnowledge Graph Software 9.0Pricing on request · 30-day trial
  2. StardogKnowledge Graph Software 8.8Free plan

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

  • Stardog — where it wins

    • Queries remote data through virtual graphs without necessarily moving it
    • Supports SPARQL, SQL, GraphQL, REST, inference, and ontology management
    • Offers both managed cloud and self-managed enterprise deployment

    Where it doesn't

    • The Free plan is limited to 1 million stored edges
    • Enterprise pricing requires contacting sales
    • It is proprietary rather than open source
  • 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 →
  • Stardog8.8/10 · Free plan

    A flexible choice for federating enterprise data across cloud, databases, and APIs.

    Visit StardogFull 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