WhoAPI

WhoAPI (founded 2011, WhoAPI Inc.) is a domain-intelligence API company that exposes WHOIS records, real-time domain availability across hundreds of TLDs, domain age, domain reputation/score, SSL certificate inspection, email score, IP/domain blacklist checks, and website screenshots through a single key-authenticated REST endpoint (api.whoapi.com). Every request is an HTTP GET selecting a task with the `r` parameter and returning gzip-compressed JSON with a numeric `status` and human-readable `status_desc`. It serves cybersecurity teams, domain registrars, SEO agencies, and fraud-detection systems, with first-party and community SDKs for Ruby, Python, Go, and R.

WhoAPI publishes 1 API on the APIs.io network: Domain Intelligence API. Tagged areas include Company, Domains, WHOIS, Domain Availability, and SSL.

The WhoAPI catalog on APIs.io includes 1 event-driven AsyncAPI specification.

WhoAPI’s developer surface includes documentation, API reference, getting-started guide, engineering blog, pricing, signup flow, CLI, and 22 more developer resources.

🌐 Visit website 📡 Source on GitHub
56.2/100 strong ▲ 10.3 Agent 47/100 agent ready Full breakdown ↓
scored 2026-08-17 · rubric v0.11.0
AccessSelf serve
1 APIs 1 MCP Servers
CompanyDomainsWHOISDomain AvailabilitySSLEmail VerificationBlacklistCybersecurityDomain IntelligenceScreenshotsReputation

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-17 · rubric v0.11.0
Composite quality — 56.2/100 · strong
Contract Quality 16.6 / 25
Developer Ergonomics 13.8 / 20
Commercial Clarity 8.9 / 20
Operational Transparency 7.9 / 13
Governance 1.4 / 12
Discoverability 7.6 / 10
Agent readiness — 47/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
MCP Server 12 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 6 / 6
Agent Skills 5 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/whoapi: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 1

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

WhoAPI Domain Intelligence API

A single HTTP GET endpoint (api.whoapi.com) exposing nine domain-intelligence tasks selected by the `r` query parameter — whois, taken (availability), cert (SSL), domainscore an...

Open Collections 2

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

API Collection

OPEN COLLECTION

WhoAPI Domain Intelligence API

OPEN COLLECTION

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

whoapi-mcp.yml

MCP SERVER

Pricing Plans 1

Published pricing tiers and plan structures.

Whoapi Plans Pricing

0 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Whoapi Rate Limits

4 limits

RATE LIMITS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Whoapi Webhooks

ASYNCAPI

Security Posture 2

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

Whoapi Authentication

apiKey · 1 scheme

SECURITY

Whoapi Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Whoapi Agentic Access

1 operation

1 operations · 0 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp
 Login
Login

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess
 MCPServer
MCPServer
 LLMsTxt
LLMsTxt
 AgentSkill
AgentSkill

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

Conformance
Conformance
 Webhooks
Webhooks

Build 5

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization
 Packages
Packages
 SDKs
SDKs
 CLI
CLI
 ToolCrosswalk
ToolCrosswalk

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication

Operate 3

Status, limits, changes, and where to get help

StatusPage
StatusPage
 Support
Support
 RateLimits
RateLimits

Commercial 4

Pricing, plans, and the legal terms of use

Pricing
Pricing
 PrivacyPolicy
PrivacyPolicy
 TermsOfService
TermsOfService
 Plans
Plans

Company 2

The organization behind the API

Website
Website
 Blog
Blog

Other 1

Properties that don't map to a standard resource type

Overlay
Overlay

Source (apis.yml)

apis.yml Raw ↑ 
aid: whoapi
name: WhoAPI
x-enrichment:
  date: '2026-08-14'
  status: enriched
  artifacts_added: 7
  pass: local-v1
description: WhoAPI (founded 2011, WhoAPI Inc.) is a domain-intelligence API company that exposes WHOIS records, real-time
  domain availability across hundreds of TLDs, domain age, domain reputation/score, SSL certificate inspection, email score,
  IP/domain blacklist checks, and website screenshots through a single key-authenticated REST endpoint (api.whoapi.com). Every
  request is an HTTP GET selecting a task with the `r` parameter and returning gzip-compressed JSON with a numeric `status`
  and human-readable `status_desc`. It serves cybersecurity teams, domain registrars, SEO agencies, and fraud-detection systems,
  with first-party and community SDKs for Ruby, Python, Go, and R.
url: https://raw.githubusercontent.com/api-evangelist/whoapi/refs/heads/main/apis.yml
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://whoapi.com/wp-content/uploads/2024/04/API-company-illustration.svg
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-08-14'
tags:
- Company
- Domains
- WHOIS
- Domain Availability
- SSL
- Email Verification
- Blacklist
- Cybersecurity
- Domain Intelligence
- Screenshots
- Reputation
apis:
- aid: whoapi:whoapi-domain-intelligence-api
  name: WhoAPI Domain Intelligence API
  description: A single HTTP GET endpoint (api.whoapi.com) exposing nine domain-intelligence tasks selected by the `r` query
    parameter — whois, taken (availability), cert (SSL), domainscore and domainscore-check, emailscore and emailscore-check,
    blacklist, and screenshot. Authenticated with an `apikey` query parameter and optional IP whitelisting. Responses are
    gzip-compressed JSON carrying a numeric `status`; errors are returned in-band with HTTP 200. The two scoring tasks are
    asynchronous and accept a `webhook_url` callback parameter.
  humanURL: https://whoapi.com/api-documentation/
  baseURL: https://api.whoapi.com/
  tags:
  - Domain Intelligence
  properties:
  - type: OpenAPI
    url: openapi/whoapi-domain-intelligence-api-openapi.yml
  - type: Documentation
    url: https://whoapi.com/api-documentation/
  - type: APIReference
    url: https://whoapi.com/api-documentation/
  - type: Authentication
    url: authentication/whoapi-authentication.yml
  - type: Conventions
    url: conventions/whoapi-conventions.yml
  - type: ErrorCatalog
    url: errors/whoapi-error-codes.yml
  - type: Lifecycle
    url: lifecycle/whoapi-lifecycle.yml
  - type: DataModel
    url: data-model/whoapi-data-model.yml
  - type: Conformance
    url: conformance/whoapi-conformance.yml
  - type: Sandbox
    url: sandbox/whoapi-sandbox.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/whoapi-agentic-access.yml
- type: MCPServer
  url: mcp/whoapi-mcp.yml
- type: Overlay
  url: overlays/whoapi-openapi-overlay.yaml
- type: DomainSecurity
  url: security/whoapi-domain-security.yml
- type: Website
  url: https://whoapi.com
- type: DeveloperPortal
  url: https://whoapi.com/api-documentation/
- type: Documentation
  url: https://whoapi.com/api-documentation/
- type: APIReference
  url: https://whoapi.com/api-documentation/
- type: GettingStarted
  url: https://whoapi.com/code-examples/
- type: Blog
  url: https://whoapi.com/blog/
- type: Pricing
  url: https://whoapi.com/whois-api-pricing/
- type: SignUp
  url: https://my.whoapi.com/user/signup
- type: Login
  url: https://my.whoapi.com/
- type: PrivacyPolicy
  url: https://whoapi.com/privacy-policy/
- type: StatusPage
  url: https://status.whoapi.com
- type: GitHubOrganization
  url: https://github.com/whoapi
- type: Packages
  url: packages/whoapi-packages.yml
- type: SDKs
  url: packages/whoapi-packages.yml
- type: CLI
  url: cli/whoapi-cli.yml
- type: Authentication
  url: authentication/whoapi-authentication.yml
- type: LLMsTxt
  url: llms/whoapi-llms.txt
- type: AgentSkill
  url: skills/_index.yml
- type: Conformance
  url: conformance/whoapi-conformance.yml
- type: TermsOfService
  url: https://whoapi.com/terms-of-use/
- type: Support
  url: https://whoapi.com/contact-us/
- type: Plans
  url: plans/whoapi-plans-pricing.yml
- type: RateLimits
  url: rate-limits/whoapi-rate-limits.yml
- type: Webhooks
  url: asyncapi/whoapi-webhooks.yml
- type: ToolCrosswalk
  url: mcp/whoapi-tool-crosswalk.yml