ChEMBL Assay API
Experimental protocols and result details from source documents and datasets.
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OpenAPI Specification
openapi: 3.2.0
info:
title: ChEMBL Data REST Activity Assay API
description: ChEMBL is a manually curated database of bioactive molecules with drug-like properties, maintained by the EMBL-EBI. This REST API provides programmatic access to bioactive molecules, drug targets, bioactivity measurements, approved drugs, assay data, and clinical trial compound information. ChEMBL_37 contains over 2.9 million distinct compounds, 24.5 million activities, and 18,552 targets.
version: ChEMBL_37
contact:
name: ChEMBL Team
email: chembl-help@ebi.ac.uk
url: https://www.ebi.ac.uk/chembl/
license:
name: Creative Commons Attribution-ShareAlike 3.0 Unported
url: https://creativecommons.org/licenses/by-sa/3.0/
termsOfService: https://www.ebi.ac.uk/about/terms-of-use/
x-logo:
url: https://www.ebi.ac.uk/chembl/static/chembl/img/chembl_logo.png
servers:
- url: https://www.ebi.ac.uk/chembl/api/data
description: ChEMBL Production API Server
tags:
- name: Assay
description: Experimental protocols and result details from source documents and datasets.
paths:
/assay:
get:
tags:
- Assay
summary: List assays
description: Retrieve a paginated list of assays. Each assay describes an experimental protocol and associated results from source documents.
operationId: listAssays
parameters:
- $ref: '#/components/parameters/format'
- $ref: '#/components/parameters/limit'
- $ref: '#/components/parameters/offset'
- name: assay_chembl_id
in: query
description: Filter by ChEMBL assay ID
schema:
type: string
- name: assay_type
in: query
description: Filter by assay type
schema:
type: string
enum:
- B
- F
- A
- T
- P
- U
- name: target_chembl_id
in: query
description: Filter by target ChEMBL ID
schema:
type: string
responses:
'200':
description: Paginated list of assays
content:
application/json:
schema:
type: object
properties:
meta:
$ref: '#/components/schemas/Meta'
assays:
type: array
items:
$ref: '#/components/schemas/Assay'
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
/assay/{assay_chembl_id}:
get:
tags:
- Assay
summary: Get assay by ChEMBL ID
description: Retrieve a single assay by its ChEMBL ID.
operationId: getAssay
parameters:
- name: assay_chembl_id
in: path
required: true
description: ChEMBL ID of the assay
schema:
type: string
example: CHEMBL1909072
- $ref: '#/components/parameters/format'
responses:
'200':
description: Assay record
content:
application/json:
schema:
$ref: '#/components/schemas/Assay'
'404':
$ref: '#/components/responses/NotFound'
components:
parameters:
offset:
name: offset
in: query
description: Number of records to skip for pagination
schema:
type: integer
default: 0
minimum: 0
limit:
name: limit
in: query
description: Number of records to return per page (default 20, max 1000)
schema:
type: integer
default: 20
maximum: 1000
minimum: 1
format:
name: format
in: query
description: Response format
schema:
type: string
enum:
- json
- xml
- yaml
- jsonp
default: json
responses:
BadRequest:
description: Bad request - invalid query parameters
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
NotFound:
description: Resource not found
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
schemas:
Assay:
type: object
description: An experimental assay describing the protocol used to measure bioactivity
properties:
assay_category:
type:
- string
- 'null'
description: Assay category (e.g., screening, confirmatory, summary)
assay_cell_type:
type:
- string
- 'null'
description: Cell type used in the assay
assay_chembl_id:
type: string
description: Unique ChEMBL ID for the assay
assay_description:
type: string
description: Description of the assay as curated from the source document
assay_organism:
type:
- string
- 'null'
description: Organism from which the assay target comes
assay_strain:
type:
- string
- 'null'
description: Strain of organism used in the assay
assay_subcellular_fraction:
type:
- string
- 'null'
description: Subcellular fraction used in the assay
assay_tax_id:
type:
- string
- 'null'
description: NCBI taxonomy ID of the assay organism
assay_tissue:
type:
- string
- 'null'
description: Tissue from which the assay is derived
assay_type:
type: string
description: Assay type code
assay_type_description:
type:
- string
- 'null'
description: Description of the assay type
bao_format:
type:
- string
- 'null'
description: BioAssay Ontology format classification
bao_label:
type:
- string
- 'null'
description: BioAssay Ontology format label
document_chembl_id:
type: string
description: ChEMBL ID of the source document
relationship_description:
type:
- string
- 'null'
description: Description of the target-assay relationship
relationship_type:
type:
- string
- 'null'
description: Relationship between the assay and its molecular target
src_assay_id:
type:
- string
- 'null'
description: Assay ID from the source database
src_id:
type:
- integer
- 'null'
description: Source database ID
target_chembl_id:
type:
- string
- 'null'
description: ChEMBL ID of the assay target
tissue_chembl_id:
type:
- string
- 'null'
description: ChEMBL ID of the tissue
variant_sequence:
type:
- string
- 'null'
description: Sequence mutation information for variant assays
Error:
type: object
properties:
error_message:
type: string
status:
type: string
Meta:
type: object
description: Pagination metadata for list responses
properties:
limit:
type: integer
description: Number of records returned per page
next:
type:
- string
- 'null'
description: URL for the next page of results
offset:
type: integer
description: Number of records skipped
previous:
type:
- string
- 'null'
description: URL for the previous page of results
total_count:
type: integer
description: Total number of records matching the query
externalDocs:
description: ChEMBL Web Services Documentation
url: https://chembl.gitbook.io/chembl-interface-documentation/web-services/chembl-data-web-services