The vocabulary stack
for healthcare data teams
APIs, SDKs, MCP server, FHIR to OMOP Resolver, FHIR Terminology Service - the full ecosystem, delivered as SaaS. No infrastructure to maintain. No vocabulary updates to chase.
Our story
“The community is energized and expanding globally, but needs infrastructure to scale.”
- Patrick Ryan · OHDSI Community Call · December 9, 2025
That observation captured exactly what we were seeing. OHDSI and OMOP adoption were growing, but the infrastructure layer around vocabularies was still too hard to operate, integrate, and scale.
OMOPHub was created to fill that gap by giving teams fast, reliable access to OMOP vocabularies through APIs and developer-friendly workflows, without requiring them to host the vocabulary stack themselves.
The stack
A foundation deserves to be a platform
Medical vocabularies are foundational to every OMOP ETL, every cohort definition, every RWE study, and increasingly every AI-driven clinical workflow. We think that foundation deserves to be a platform, not a pile of downloads, cron jobs, and private forks.
OMOPHub is a complete vocabulary stack - accessible from any language, integrated with every tool that needs it, and kept current without your team lifting a finger.
Available today
REST API
11M+ standardized concepts across 100+ terminologies.
api.omophub.com
Python & R SDKs
Typed clients for scripting, notebooks, ETL pipelines, and native OHDSI analytics workflows.
PyPI · CRAN
MCP Server
Hosted. Connect Claude, Cursor, VS Code, or Windsurf with one URL and an API key.
Hosted
FHIR to OMOP Resolver
Resolve a FHIR Coding to its OMOP standard concept and target CDM table in one call.
POST /fhir/resolve
FHIR terminology service
CodeSystem and ValueSet endpoints for FHIR-native applications.
R4 · R4B · R5 · R6
Semantic search
Find the concept you mean, even when you don't know the code.
Hosted embeddings
On the roadmap
JavaScript / TypeScript SDK
SoonTyped client for Node, browsers, and edge runtimes.
npm
Collaborative ConceptSets
SoonShared definitions with version control and audit trails, so teams stop re-inventing cohort logic in private spreadsheets.
One platform. Updated continuously. Accessed with an API key.
Who builds with OMOPHub
More than 250 teams
already build with OMOPHub
Research groups, ETL developers, RWE/HEOR teams, and AI product builders use OMOPHub for day-to-day vocabulary work - from academic ETL projects to LLM-driven clinical analysis in industry.
That includes pipelines preparing for European Health Data Space secondary use, where OMOP CDM is the recommended semantic standard and the vocabulary layer has to be rock solid.
Who's behind it
A small, focused operation. By design.
It started as a small team, and a conviction that the OHDSI community deserves first-class infrastructure together with excelent developer experience.
Today it's still a small team and a tight roadmap: fast APIs, reliable data, clear docs, and deliberate scope.
If the shape of the problem resonates or you have ideas for improvements, get in touch.
— Alex Chen, Founder