EMBL-EBI Ontology Lookup Service (OLS) API

REST API providing access to a curated repository of biomedical ontologies, enabling search and retrieval of ontology terms, properties, and hierarchical relationships across multiple ontology vocabularies.

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Slug: embl-ebi-ontology-lookup-service-ols
Key: ac.uk:embl-ebi-ontology-lookup-service-ols-api
Base URL: https://www.ebi.ac.uk/ols4/api
Auth: none
Endpoints: 37
Reachable: yes
CORS: unknown
Tier: verified
Last checked: 2026-03-14 16:08:09.388405

Links

Homepage: https://www.ebi.ac.uk/ols4/
API Base: https://www.ebi.ac.uk/ols4/api

Topics

BIOINFORMATICS, KNOWLEDGE, SCIENCE

Endpoints (37)

Path Summary Response Auth
Get API root with available resources application/json none
individuals List all individuals application/json none
ontologies List all ontologies application/json none
ontologies/{ontologyId} Get ontology by ID application/json none
ontologies/{ontologyId}/individuals List individuals in an ontology application/json none
ontologies/{ontologyId}/individuals/{individualId} Get individual details application/json none
ontologies/{ontologyId}/properties List properties in an ontology application/json none
ontologies/{ontologyId}/properties/{propertyId} Get property details application/json none
ontologies/{ontologyId}/terms Get terms from an ontology application/json none
ontologies/{ontologyId}/terms/{iri} Get specific term by IRI application/json none
ontologies/{ontologyId}/terms/{iri}/ancestors Get all ancestors of a term text/html none
ontologies/{ontologyId}/terms/{iri}/children Get children of a term text/html none
ontologies/{ontologyId}/terms/{iri}/descendants Get all descendants of a term text/html none
ontologies/{ontologyId}/terms/{iri}/graph Get term graph ? none
ontologies/{ontologyId}/terms/{iri}/hierarchicalAncestors Get hierarchical ancestor terms application/json none
ontologies/{ontologyId}/terms/{iri}/hierarchicalChildren Get hierarchical child terms application/json none
ontologies/{ontologyId}/terms/{iri}/hierarchicalParents Get hierarchical parent terms application/json none
ontologies/{ontologyId}/terms/{iri}/jstree Get jsTree representation ? none
ontologies/{ontologyId}/terms/{iri}/parents Get parents of a term text/html none
ontologies/{ontologyId}/terms/{termId} Get term details application/json none
ontologies/{ontologyId}/terms/{termId}/ancestors Get term ancestors application/json none
ontologies/{ontologyId}/terms/{termId}/children Get term children application/json none
ontologies/{ontologyId}/terms/{termId}/descendants Get term descendants application/json none
ontologies/{ontologyId}/terms/{termId}/hierarchicalAncestors Get hierarchical ancestors application/json none
ontologies/{ontologyId}/terms/{termId}/hierarchicalChildren Get hierarchical children application/json none
ontologies/{ontologyId}/terms/{termId}/hierarchicalDescendants Get hierarchical descendants application/json none
ontologies/{ontologyId}/terms/{termId}/hierarchicalParents Get hierarchical parents application/json none
ontologies/{ontologyId}/terms/{termId}/jstree Get JS Tree representation ? none
ontologies/{ontologyId}/terms/{termId}/parents Get term parents application/json none
ontologies/{ontology_id} Get ontology details application/json none
ontologies/{ontology_id}/terms Get ontology terms application/json none
properties List all properties application/json none
search Search for terms application/json none
select Autocomplete/select suggestions application/json none
suggest Suggest terms application/json none
terms Search across all ontologies application/json none
terms/{iri} Get term by IRI application/json none