Let's Encrypt

Let's Encrypt Directory API

Discovery document listing ACME resources

GitHub OpenAPI

Operations 1

1 of 1 operations are conformant: apis.io called them with no credentials and the responses matched this contract. Checked 2026-11-12. how this works · status file

GET /directory Get ACME directory conformant #

Documentation

📖
Documentation
https://letsencrypt.org/docs/

Specifications

⚙
OpenAPI
https://artifacts.apis.io/lets-encrypt/openapi/lets-encrypt-directory-api-openapi.yml

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OpenAPI Specification

lets-encrypt-directory-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Let's Encrypt ACME Directory API
  description: The ACME (Automatic Certificate Management Environment) protocol API used by Let's Encrypt to automate the issuance, renewal, and revocation of TLS certificates. Implements RFC 8555.
  version: '1.0'
  contact:
    name: Let's Encrypt
    url: https://letsencrypt.org/docs/
  license:
    name: Mozilla Public License 2.0
    url: https://www.mozilla.org/en-US/MPL/2.0/
servers:
- url: https://acme-v02.api.letsencrypt.org
  description: Production ACME endpoint
- url: https://acme-staging-v02.api.letsencrypt.org
  description: Staging ACME endpoint
tags:
- name: Directory
  description: Discovery document listing ACME resources
paths:
  /directory:
    get:
      tags:
      - Directory
      summary: Get ACME directory
      description: Returns URLs for all ACME resources and server metadata.
      operationId: getDirectory
      responses:
        '200':
          description: Directory object
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Directory'
components:
  schemas:
    Directory:
      type: object
      properties:
        newNonce:
          type: string
          format: uri
        newAccount:
          type: string
          format: uri
        newOrder:
          type: string
          format: uri
        newAuthz:
          type: string
          format: uri
        revokeCert:
          type: string
          format: uri
        keyChange:
          type: string
          format: uri
        meta:
          type: object
          properties:
            termsOfService:
              type: string
            website:
              type: string
            caaIdentities:
              type: array
              items:
                type: string