Clerk

Clerk is a drop-in authentication and user management platform for web and mobile applications. The product spans sign-up / sign-in flows, user profiles, multi-factor authentication, passkeys, social sign-on, magic links, bot and fraud detection, organizations (B2B / multi-tenant) with custom roles and invitations, and a Billing product for subscriptions. The Backend API at api.clerk.com is authenticated with a Bearer secret key and has an OpenAPI specification. Frontend SDKs cover Next.js, React, React Router, Expo, Astro, TanStack React Start, Chrome Extension, and vanilla JavaScript. Backend SDKs cover Node, Go, Python, Ruby, Java, PHP, and C#. Webhooks are delivered via Svix.

Clerk publishes 8 APIs on the APIs.io network, including Webhooks (Svix), Invitations API, JwtTemplates API, and 5 more. Tagged areas include Authentication, User Management, Identity, Passkeys, and MFA.

The Clerk catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

Clerk’s developer surface includes authentication, documentation, GitHub presence, pricing, changelog, engineering blog, status page, and 6 more developer resources.

🌐 Visit website 📡 Source on GitHub

47.3/100 developing ▬ flat Agent 36/100 agent ready Full breakdown ↓
scored 2026-07-28 · rubric v0.6

AccessFreeSelf serve⚡ Free to try

24 APIs

AuthenticationUser ManagementIdentityPasskeysMFAB2BOrganizationsBilling

Kin Score

Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6

Composite quality — 47.3/100 · developing

Contract Quality 17.2 / 25

Developer Ergonomics 4.3 / 20

Commercial Clarity 7.9 / 20

Operational Transparency 5.5 / 13

Governance 5.0 / 12

Discoverability 7.4 / 10

Agent readiness — 36/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

MCP Server 0 / 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 0 / 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/clerk: 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 24

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

Clerk Frontend API

Browser-facing API consumed by Clerk's frontend SDKs and ClerkJS for sign-up, sign-in, session refresh, and user profile mutations. Endpoint is instance-specific (subdomain on c...

Clerk Webhooks (Svix)

Webhook events delivered via Svix for user, session, organization, email, SMS, and role lifecycle changes. Customers configure endpoints in the dashboard and verify signatures w...

Clerk JavaScript SDK

Official ClerkJS browser library and monorepo of framework adapters (Next.js, React, Expo, React Router, Astro, Chrome Extension, TanStack). Powers Clerk's prebuilt UI component...

Clerk Next.js SDK

Next.js integration covering App Router and Pages Router, middleware, route handlers, server components, and server actions. Distributed from the @clerk/nextjs package inside th...

Clerk React SDK

React components, hooks, and providers from the @clerk/clerk-react package for plain React SPAs.

Clerk Expo SDK

Expo / React Native bindings for Clerk supporting OAuth via deep links, secure session storage, and biometrics.

Clerk React Router SDK

Adapter for React Router v7 (Remix successor) covering loaders, actions, and server-rendered authentication.

Clerk Astro SDK

Adapter for the Astro framework with components and middleware.

Clerk TanStack Start SDK

Adapter for TanStack Start (React full-stack framework) with route-level authentication helpers.

Clerk Node.js SDK

Backend SDK for Node.js (@clerk/backend / @clerk/express / @clerk/fastify) that wraps the Backend API and verifies session JWTs.

Clerk Go SDK

Official Go SDK for the Clerk Backend API.

Clerk Python SDK

Official Python SDK for the Clerk Backend API.

Clerk Ruby SDK

Official Ruby SDK for the Clerk Backend API, with a Rails integration.

Clerk Java SDK

Official Java SDK for the Clerk Backend API.

Clerk PHP SDK

Official PHP SDK for the Clerk Backend API.

Clerk C# / .NET SDK

Official C# / .NET SDK for the Clerk Backend API.

Clerk OpenAPI Specifications

Public repository of OpenAPI specifications for Clerk's APIs, used as the source for generated SDKs and documentation.

Clerk Invitations API

The Invitations API from Clerk — 2 operation(s) for invitations.

Clerk JwtTemplates API

The JwtTemplates API from Clerk — 1 operation(s) for jwttemplates.

Clerk Organizations API

The Organizations API from Clerk — 4 operation(s) for organizations.

Clerk Sessions API

The Sessions API from Clerk — 4 operation(s) for sessions.

Clerk SignInTokens API

The SignInTokens API from Clerk — 2 operation(s) for signintokens.

Clerk Users API

The Users API from Clerk — 4 operation(s) for users.

Clerk Webhooks API

The Webhooks API from Clerk — 1 operation(s) for webhooks.

Scroll for all 24

Open Collections 1

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

Clerk Backend API

OPEN COLLECTION

GraphQL 1

GraphQL schemas published by this provider.

Rate Limits 1

Documented rate limits and quota policies.

Clerk Rate Limits

2 limits

RATE LIMITS

FinOps 1

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

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LlmsText

LlmsText

Build 1

SDKs, sample code, and the tooling you integrate with

GitHub

GitHub

Access & Security 3

Authentication, authorization, and security posture

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 2

Status, limits, changes, and where to get help

ChangeLog

ChangeLog

Status

Status

Commercial 1

Pricing, plans, and the legal terms of use

Pricing

Pricing

Company 3

The organization behind the API

Website

Website

Blog

Blog

LinkedIn

Source (apis.yml)

aid: clerk
url: https://raw.githubusercontent.com/api-evangelist/clerk/refs/heads/main/apis.yml
name: Clerk
kind: company
description: Clerk is a drop-in authentication and user management platform for web and mobile applications. The product spans
  sign-up / sign-in flows, user profiles, multi-factor authentication, passkeys, social sign-on, magic links, bot and fraud
  detection, organizations (B2B / multi-tenant) with custom roles and invitations, and a Billing product for subscriptions.
  The Backend API at api.clerk.com is authenticated with a Bearer secret key and has an OpenAPI specification. Frontend SDKs
  cover Next.js, React, React Router, Expo, Astro, TanStack React Start, Chrome Extension, and vanilla JavaScript. Backend
  SDKs cover Node, Go, Python, Ruby, Java, PHP, and C#. Webhooks are delivered via Svix.
accessModel:
  pricing: free
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Free · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/clerk.png
tags:
- Authentication
- User Management
- Identity
- Passkeys
- MFA
- B2B
- Organizations
- Billing
created: '2026-05-23'
modified: '2026-05-30'
specificationVersion: '0.19'
apis:
- aid: clerk:frontend-api
  name: Clerk Frontend API
  description: Browser-facing API consumed by Clerk's frontend SDKs and ClerkJS for sign-up, sign-in, session refresh, and
    user profile mutations. Endpoint is instance-specific (subdomain on clerk.accounts.dev or a customer vanity domain). Authenticated
    with the publishable key and short-lived client tokens.
  humanURL: https://clerk.com/docs/reference/frontend-api
  baseURL: https://clerk.accounts.dev
  tags:
  - Frontend
  - REST
  - Sessions
  properties:
  - type: Documentation
    url: https://clerk.com/docs/reference/frontend-api
- aid: clerk:webhooks
  name: Clerk Webhooks (Svix)
  description: Webhook events delivered via Svix for user, session, organization, email, SMS, and role lifecycle changes.
    Customers configure endpoints in the dashboard and verify signatures with the Svix libraries.
  humanURL: https://clerk.com/docs/integrations/webhooks/overview
  baseURL: customer-configured
  tags:
  - Webhooks
  - Events
  - Svix
  properties:
  - type: Documentation
    url: https://clerk.com/docs/integrations/webhooks/overview
  - type: AsyncAPI
    url: https://raw.githubusercontent.com/api-evangelist/clerk/refs/heads/main/asyncapi/clerk-webhooks-asyncapi.yml
- aid: clerk:javascript
  name: Clerk JavaScript SDK
  description: Official ClerkJS browser library and monorepo of framework adapters (Next.js, React, Expo, React Router, Astro,
    Chrome Extension, TanStack). Powers Clerk's prebuilt UI components and headless hooks.
  humanURL: https://github.com/clerk/javascript
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - JavaScript
  - Frontend
  properties:
  - type: Repository
    url: https://github.com/clerk/javascript
- aid: clerk:sdk-nextjs
  name: Clerk Next.js SDK
  description: Next.js integration covering App Router and Pages Router, middleware, route handlers, server components, and
    server actions. Distributed from the @clerk/nextjs package inside the JavaScript monorepo.
  humanURL: https://clerk.com/docs/quickstarts/nextjs
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - Next.js
  - Frontend
  properties:
  - type: Documentation
    url: https://clerk.com/docs/quickstarts/nextjs
- aid: clerk:sdk-react
  name: Clerk React SDK
  description: React components, hooks, and providers from the @clerk/clerk-react package for plain React SPAs.
  humanURL: https://clerk.com/docs/quickstarts/react
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - React
  - Frontend
  properties:
  - type: Documentation
    url: https://clerk.com/docs/quickstarts/react
- aid: clerk:sdk-expo
  name: Clerk Expo SDK
  description: Expo / React Native bindings for Clerk supporting OAuth via deep links, secure session storage, and biometrics.
  humanURL: https://clerk.com/docs/quickstarts/expo
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - Expo
  - React Native
  - Mobile
  properties:
  - type: Documentation
    url: https://clerk.com/docs/quickstarts/expo
- aid: clerk:sdk-react-router
  name: Clerk React Router SDK
  description: Adapter for React Router v7 (Remix successor) covering loaders, actions, and server-rendered authentication.
  humanURL: https://clerk.com/docs/quickstarts/react-router
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - React Router
  - Frontend
  properties:
  - type: Documentation
    url: https://clerk.com/docs/quickstarts/react-router
- aid: clerk:sdk-astro
  name: Clerk Astro SDK
  description: Adapter for the Astro framework with components and middleware.
  humanURL: https://clerk.com/docs/quickstarts/astro
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - Astro
  - Frontend
  properties:
  - type: Documentation
    url: https://clerk.com/docs/quickstarts/astro
- aid: clerk:sdk-tanstack-start
  name: Clerk TanStack Start SDK
  description: Adapter for TanStack Start (React full-stack framework) with route-level authentication helpers.
  humanURL: https://clerk.com/docs/quickstarts/tanstack-start
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - TanStack
  - Frontend
  properties:
  - type: Documentation
    url: https://clerk.com/docs/quickstarts/tanstack-start
- aid: clerk:sdk-node
  name: Clerk Node.js SDK
  description: Backend SDK for Node.js (@clerk/backend / @clerk/express / @clerk/fastify) that wraps the Backend API and verifies
    session JWTs.
  humanURL: https://clerk.com/docs/references/backend/overview
  baseURL: https://github.com/clerk/javascript
  tags:
  - SDK
  - Node.js
  - Backend
  properties:
  - type: Documentation
    url: https://clerk.com/docs/references/backend/overview
- aid: clerk:sdk-go
  name: Clerk Go SDK
  description: Official Go SDK for the Clerk Backend API.
  humanURL: https://github.com/clerk/clerk-sdk-go
  baseURL: https://github.com/clerk/clerk-sdk-go
  tags:
  - SDK
  - Go
  - Backend
  properties:
  - type: Repository
    url: https://github.com/clerk/clerk-sdk-go
- aid: clerk:sdk-python
  name: Clerk Python SDK
  description: Official Python SDK for the Clerk Backend API.
  humanURL: https://github.com/clerk/clerk-sdk-python
  baseURL: https://github.com/clerk/clerk-sdk-python
  tags:
  - SDK
  - Python
  - Backend
  properties:
  - type: Repository
    url: https://github.com/clerk/clerk-sdk-python
- aid: clerk:sdk-ruby
  name: Clerk Ruby SDK
  description: Official Ruby SDK for the Clerk Backend API, with a Rails integration.
  humanURL: https://github.com/clerk/clerk-sdk-ruby
  baseURL: https://github.com/clerk/clerk-sdk-ruby
  tags:
  - SDK
  - Ruby
  - Rails
  - Backend
  properties:
  - type: Repository
    url: https://github.com/clerk/clerk-sdk-ruby
- aid: clerk:sdk-java
  name: Clerk Java SDK
  description: Official Java SDK for the Clerk Backend API.
  humanURL: https://github.com/clerk/clerk-sdk-java
  baseURL: https://github.com/clerk/clerk-sdk-java
  tags:
  - SDK
  - Java
  - Backend
  properties:
  - type: Repository
    url: https://github.com/clerk/clerk-sdk-java
- aid: clerk:sdk-php
  name: Clerk PHP SDK
  description: Official PHP SDK for the Clerk Backend API.
  humanURL: https://github.com/clerk/clerk-sdk-php
  baseURL: https://github.com/clerk/clerk-sdk-php
  tags:
  - SDK
  - PHP
  - Backend
  properties:
  - type: Repository
    url: https://github.com/clerk/clerk-sdk-php
- aid: clerk:sdk-csharp
  name: Clerk C# / .NET SDK
  description: Official C# / .NET SDK for the Clerk Backend API.
  humanURL: https://github.com/clerk/clerk-sdk-csharp
  baseURL: https://github.com/clerk/clerk-sdk-csharp
  tags:
  - SDK
  - .NET
  - C#
  - Backend
  properties:
  - type: Repository
    url: https://github.com/clerk/clerk-sdk-csharp
- aid: clerk:openapi-specs
  name: Clerk OpenAPI Specifications
  description: Public repository of OpenAPI specifications for Clerk's APIs, used as the source for generated SDKs and documentation.
  humanURL: https://github.com/clerk/openapi-specs
  baseURL: https://github.com/clerk/openapi-specs
  tags:
  - OpenAPI
  - Specifications
  properties:
  - type: Repository
    url: https://github.com/clerk/openapi-specs
- aid: clerk:clerk-invitations-api
  name: Clerk Invitations API
  description: The Invitations API from Clerk — 2 operation(s) for invitations.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - Invitations
  properties:
  - type: OpenAPI
    url: openapi/clerk-invitations-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
- aid: clerk:clerk-jwttemplates-api
  name: Clerk JwtTemplates API
  description: The JwtTemplates API from Clerk — 1 operation(s) for jwttemplates.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - JwtTemplates
  properties:
  - type: OpenAPI
    url: openapi/clerk-jwttemplates-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
- aid: clerk:clerk-organizations-api
  name: Clerk Organizations API
  description: The Organizations API from Clerk — 4 operation(s) for organizations.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - Organizations
  properties:
  - type: OpenAPI
    url: openapi/clerk-organizations-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
- aid: clerk:clerk-sessions-api
  name: Clerk Sessions API
  description: The Sessions API from Clerk — 4 operation(s) for sessions.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - Sessions
  properties:
  - type: OpenAPI
    url: openapi/clerk-sessions-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
- aid: clerk:clerk-signintokens-api
  name: Clerk SignInTokens API
  description: The SignInTokens API from Clerk — 2 operation(s) for signintokens.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - SignInTokens
  properties:
  - type: OpenAPI
    url: openapi/clerk-signintokens-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
- aid: clerk:clerk-users-api
  name: Clerk Users API
  description: The Users API from Clerk — 4 operation(s) for users.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - Users
  properties:
  - type: OpenAPI
    url: openapi/clerk-users-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
- aid: clerk:clerk-webhooks-api
  name: Clerk Webhooks API
  description: The Webhooks API from Clerk — 1 operation(s) for webhooks.
  humanURL: https://clerk.com/docs/reference/backend-api
  baseURL: https://api.clerk.com
  tags:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/clerk-webhooks-api-openapi.yml
  - type: Documentation
    url: https://clerk.com/docs/reference/backend-api
  - type: GraphQL
    url: graphql/clerk-graphql.md
common:
- type: AgenticAccess
  url: agentic-access/clerk-agentic-access.yml
- type: VulnerabilityDisclosure
  url: security/clerk-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/clerk-domain-security.yml
- type: Authentication
  url: authentication/clerk-authentication.yml
- type: Website
  url: https://clerk.com/
- type: Documentation
  url: https://clerk.com/docs
- type: GitHub
  url: https://github.com/clerk
- type: Pricing
  url: https://clerk.com/pricing
- type: ChangeLog
  url: https://clerk.com/changelog
- type: Blog
  url: https://clerk.com/blog
- type: Status
  url: https://status.clerk.com/
- type: LinkedIn
  url: https://www.linkedin.com/company/clerk-dev/
- type: LlmsText
  url: https://clerk.com/llms.txt
integrations:
- name: Next.js
- name: React
- name: Expo
- name: Astro
- name: TanStack
- name: Supabase
- name: Convex
- name: Vercel
- name: Svix
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com