EMBL-EBI Ontology Lookup Service (OLS) API

The Ontology Lookup Service (OLS) provides a web service interface to query multiple ontologies from a single location with a unified output format. OLS can be used to browse ontologies via the website or programmatically via the REST API. This is the OLS4 API which provides access to over 200 ontologies from OBO and other sources.

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Base URL: https://www.ebi.ac.uk/ols4/api/
Auth: none
Endpoints: 37
Reachable: yes
CORS: unknown
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/

100.0%

Uptime (7d)

347ms

Avg latency (7d)

45

Probes (7d)

Latency (7d)

Success Rate (7d)

Endpoints

Method Path Summary Auth Last Status Latency
GET / API Root 200 140ms
GET /individuals List all individuals 200 242ms
GET /ontologies List all ontologies 200 144ms
GET /ontologies/{ontologyId} Get ontology details 200 150ms
GET /ontologies/{ontologyId}/individuals List individuals in an ontology 200 184ms
GET /ontologies/{ontologyId}/individuals/{individualId} Get individual details
GET /ontologies/{ontologyId}/properties List properties in an ontology 200 210ms
GET /ontologies/{ontologyId}/properties/{propertyId} Get property details
GET /ontologies/{ontologyId}/terms List terms in an ontology 200 1008ms
GET /ontologies/{ontologyId}/terms/{iri} Get specific term
GET /ontologies/{ontologyId}/terms/{iri}/ancestors Get ancestor terms 400 145ms
GET /ontologies/{ontologyId}/terms/{iri}/children Get child terms 400 172ms
GET /ontologies/{ontologyId}/terms/{iri}/descendants Get descendant terms 400 145ms
GET /ontologies/{ontologyId}/terms/{iri}/graph Get term graph
GET /ontologies/{ontologyId}/terms/{iri}/hierarchicalAncestors Get hierarchical ancestor terms
GET /ontologies/{ontologyId}/terms/{iri}/hierarchicalChildren Get hierarchical child terms
GET /ontologies/{ontologyId}/terms/{iri}/hierarchicalParents Get hierarchical parent terms
GET /ontologies/{ontologyId}/terms/{iri}/jstree Get jsTree representation
GET /ontologies/{ontologyId}/terms/{iri}/parents Get parent terms 400 136ms
GET /ontologies/{ontologyId}/terms/{termId} Get term details
GET /ontologies/{ontologyId}/terms/{termId}/ancestors Get term ancestors
GET /ontologies/{ontologyId}/terms/{termId}/children Get term children
GET /ontologies/{ontologyId}/terms/{termId}/descendants Get term descendants
GET /ontologies/{ontologyId}/terms/{termId}/hierarchicalAncestors Get hierarchical ancestors
GET /ontologies/{ontologyId}/terms/{termId}/hierarchicalChildren Get hierarchical children
GET /ontologies/{ontologyId}/terms/{termId}/hierarchicalDescendants Get hierarchical descendants
GET /ontologies/{ontologyId}/terms/{termId}/hierarchicalParents Get hierarchical parents
GET /ontologies/{ontologyId}/terms/{termId}/jstree Get JS Tree representation
GET /ontologies/{ontologyId}/terms/{termId}/parents Get term parents
GET /ontologies/{ontology_id} Get ontology details
GET /ontologies/{ontology_id}/terms Get ontology terms
GET /properties List all properties 200 222ms
GET /search Search across ontologies 200 309ms
GET /select Autocomplete/select terms 200 1840ms
GET /suggest Suggest terms 200 270ms
GET /terms List all terms 200 1153ms
GET /terms/{iri} Get term by IRI 404 139ms