STRING website screenshot

STRING

STRING is a protein-protein interaction network database providing scored associations between proteins across thousands of organisms. The REST API enables programmatic access to interaction scores, network visualizations, functional enrichment analysis, homology data, and protein annotations. STRING integrates data from genomic context, co-expression, text mining, biochemical and genetic experiments, and curated databases.

STRING publishes 7 APIs on the APIs.io network, including Annotation API, Enrichment API, Homology API, and 4 more. Tagged areas include Bioinformatics, Proteins, Genomics, Life Sciences, and Research.

The STRING catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

35.9/100 thin ▬ flat Agent 21/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0
AccessFree
1 APIs
BioinformaticsProteinsGenomicsLife SciencesResearchOpen Data

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Regulatory Posture applies to this provider. Its tags matched the Health regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.
Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.
The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/string-db: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 7

Individual APIs this provider publishes, each with its own machine-readable definition.

STRING Annotation API

Functional annotations and term lookup

STRING Enrichment API

Functional enrichment analysis

STRING Homology API

Protein homology and similarity scores

STRING Identifiers API

Map protein names and synonyms to STRING identifiers

STRING Network API

Retrieve protein-protein interaction networks

STRING Utility API

Utility endpoints (version, links, API key)

STRING Valuesranks API

Values/Ranks GSEA-like enrichment (requires API key)

Scroll for all 7

Open Collections 8

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

STRING REST Homology API

OPEN COLLECTION

STRING REST Network API

OPEN COLLECTION

STRING REST Utility API

OPEN COLLECTION

Scroll for all 8

Pricing Plans 1

Published pricing tiers and plan structures.

Plans

2 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Rate Limits

2 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

context Context

0 classes · 38 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

STRING API Rules

5 rules · 3 warnings 2 info

SPECTRAL

JSON Schema 3

Standalone JSON Schema definitions for this provider's data models.

EnrichmentResult

10 properties

JSON SCHEMA

Interaction

13 properties

JSON SCHEMA

StringIdMapping

6 properties

JSON SCHEMA

Examples 4

Example request and response payloads for these APIs.

Functional Enrichment

3 fields

EXAMPLE

Get Interaction Partners

3 fields

EXAMPLE

Get String Ids

3 fields

EXAMPLE

Ppi Enrichment

3 fields

EXAMPLE

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

String Db Domain Security

TLSv1.3

SECURITY

Resources

Documentation 2

Reference material describing how the API behaves

Access & Security 1

Authentication, authorization, and security posture

Commercial 1

Pricing, plans, and the legal terms of use

Company 1

The organization behind the API

Other 2

Properties that don't map to a standard resource type

Source (apis.yml)

apis.yml Raw ↑
name: STRING
description: 'STRING is a protein-protein interaction network database providing scored associations between proteins across
  thousands of organisms. The REST API enables programmatic access to interaction scores, network visualizations, functional
  enrichment analysis, homology data, and protein annotations. STRING integrates data from genomic context, co-expression,
  text mining, biochemical and genetic experiments, and curated databases.

  '
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
specificationVersion: '0.23'
accessModel:
  pricing: free
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Free
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://string-db.org/images/logo/logo_medium.png
tags:
- Bioinformatics
- Proteins
- Genomics
- Life Sciences
- Research
- Open Data
url: https://string-db.org
apis:
- aid: string-db:string-db-annotation-api
  name: STRING Annotation API
  description: Functional annotations and term lookup
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - Annotation
  tags_raw:
  - annotation
  properties:
  - type: OpenAPI
    url: openapi/string-db-annotation-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
- aid: string-db:string-db-enrichment-api
  name: STRING Enrichment API
  description: Functional enrichment analysis
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - Enrichment
  tags_raw:
  - enrichment
  properties:
  - type: OpenAPI
    url: openapi/string-db-enrichment-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
- aid: string-db:string-db-homology-api
  name: STRING Homology API
  description: Protein homology and similarity scores
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - Homology
  tags_raw:
  - homology
  properties:
  - type: OpenAPI
    url: openapi/string-db-homology-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
- aid: string-db:string-db-identifiers-api
  name: STRING Identifiers API
  description: Map protein names and synonyms to STRING identifiers
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - Identifiers
  tags_raw:
  - identifiers
  properties:
  - type: OpenAPI
    url: openapi/string-db-identifiers-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
- aid: string-db:string-db-network-api
  name: STRING Network API
  description: Retrieve protein-protein interaction networks
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - Network
  tags_raw:
  - network
  properties:
  - type: OpenAPI
    url: openapi/string-db-network-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
- aid: string-db:string-db-utility-api
  name: STRING Utility API
  description: Utility endpoints (version, links, API key)
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - Utility
  tags_raw:
  - utility
  properties:
  - type: OpenAPI
    url: openapi/string-db-utility-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
- aid: string-db:string-db-valuesranks-api
  name: STRING Valuesranks API
  description: Values/Ranks GSEA-like enrichment (requires API key)
  humanURL: https://string-db.org/help/api/
  baseURL: https://string-db.org
  tags:
  - valuesranks
  properties:
  - type: OpenAPI
    url: openapi/string-db-valuesranks-api-openapi.yml
  - type: Documentation
    url: https://string-db.org/help/api/
common:
- type: Website
  url: https://www.string-db.org/
- type: DomainSecurity
  url: security/string-db-domain-security.yml
- type: TermsOfService
  url: https://string-db.org/cgi/info?footer_active_subpage=cookies
- type: Licensing
  url: https://string-db.org/cgi/access?footer_active_subpage=licensing
- type: UsageGuidelines
  url: https://string-db.org/cgi/access?footer_active_subpage=usage
- type: APIDocumentation
  url: https://string-db.org/help/api/
- type: Downloads
  url: https://string-db.org/cgi/download
modified: 2026-06-13
maintainers:
- FN: STRING Consortium
  url: https://string-db.org

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for providers

9 MCP tools reach this
  • find_providersBrowse and filter every provider in the catalog.
  • get_provider_artifactsEvery artifact this provider publishes, grouped by type.
  • get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
  • get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
  • get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
  • get_provider_ratingPRO — composite, band, trend and facet scores.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools →

Call it yourself

curl for this page
This provider
curl "https://apis.io/api/v1/providers/string-db"
All providers
curl "https://apis.io/api/v1/providers?limit=25"
Every operation they expose
curl "https://apis.io/api/v1/providers/string-db/operations?limit=25"
How their score was established
curl "https://apis.io/api/v1/providers/string-db/evidence"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

A second provider on the same verified email joins the account you already have.