{
  "openapi": "3.0.2",
  "info": {
    "title": "Australian ABN ACN Checksum Validator",
    "version": "1.0.0",
    "description": "Validate Australian ABN and ACN formats and checksums. Send up to 100 items in one request. This API checks number structure only. It does not query ABN Lookup, ASIC or another registry. A valid checksum does not prove assignment, registration, ownership, entity status or current registry status.\n\nThis is a best-effort service with no SLA. Requests pass through RapidAPI and may appear in RapidAPI traffic logs, including request and response content. The Worker processes requests in memory and does not independently persist them. Do not submit credentials, secrets, or confidential or non-public personal data as item values.\n\nThis independent API is not affiliated with, sponsored by or endorsed by the Australian Taxation Office, the Registrar of the Australian Business Register, the Australian Business Register or the Australian Securities and Investments Commission. Sources: https://abr.business.gov.au/Help/AbnFormat and https://download.asic.gov.au/media/v33pqqwu/datastream-messages-specification-4-aug-2025.pdf\n\nAccess: subscribe through RapidAPI, then send both x-rapidapi-key and x-rapidapi-host. Never publish a consumer key."
  },
  "paths": {
    "/au-business/validate": {
      "post": {
        "operationId": "validateAustralianBusinessNumbers",
        "summary": "Validate ABN or ACN checksums",
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": [
                  "items"
                ],
                "properties": {
                  "items": {
                    "type": "array",
                    "minItems": 1,
                    "maxItems": 100,
                    "items": {
                      "oneOf": [
                        {
                          "type": "string",
                          "maxLength": 32
                        },
                        {
                          "type": "object",
                          "required": [
                            "value"
                          ],
                          "properties": {
                            "value": {
                              "type": "string",
                              "maxLength": 32
                            },
                            "type": {
                              "type": "string",
                              "enum": [
                                "ABN",
                                "ACN"
                              ]
                            }
                          },
                          "additionalProperties": false
                        }
                      ]
                    }
                  }
                },
                "additionalProperties": false
              },
              "example": {
                "items": [
                  "51 824 753 556",
                  {
                    "value": "004 085 616",
                    "type": "ACN"
                  }
                ]
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Per-item structural checksum results; registryChecked is always false",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "required": [
                    "results",
                    "meta"
                  ],
                  "properties": {
                    "results": {
                      "type": "array",
                      "items": {
                        "type": "object"
                      }
                    },
                    "meta": {
                      "$ref": "#/components/schemas/Meta"
                    }
                  }
                }
              }
            }
          },
          "400": {
            "$ref": "#/components/responses/Error"
          },
          "401": {
            "$ref": "#/components/responses/RapidApiRejected"
          },
          "413": {
            "$ref": "#/components/responses/Error"
          },
          "415": {
            "$ref": "#/components/responses/Error"
          }
        },
        "parameters": [
          {
            "$ref": "#/components/parameters/RapidApiHost"
          }
        ]
      }
    }
  },
  "components": {
    "schemas": {
      "Meta": {
        "type": "object",
        "required": [
          "bestEffort",
          "sla"
        ],
        "properties": {
          "bestEffort": {
            "type": "boolean",
            "enum": [
              true
            ]
          },
          "sla": {
            "type": "boolean",
            "enum": [
              false
            ]
          }
        }
      }
    },
    "responses": {
      "Error": {
        "description": "Rejected request",
        "content": {
          "application/json": {
            "schema": {
              "type": "object"
            }
          }
        }
      },
      "RapidApiRejected": {
        "description": "RapidAPI rejected missing or invalid consumer authentication headers.",
        "content": {
          "application/json": {
            "schema": {
              "type": "object"
            }
          }
        }
      }
    },
    "securitySchemes": {
      "RapidApiKey": {
        "type": "apiKey",
        "in": "header",
        "name": "x-rapidapi-key",
        "description": "RapidAPI consumer key. Subscribe to this API on RapidAPI before calling it."
      }
    },
    "parameters": {
      "RapidApiHost": {
        "name": "x-rapidapi-host",
        "in": "header",
        "required": true,
        "description": "RapidAPI gateway host for this API.",
        "schema": {
          "type": "string",
          "enum": [
            "australian-abn-acn-checksum.p.rapidapi.com"
          ],
          "default": "australian-abn-acn-checksum.p.rapidapi.com"
        },
        "example": "australian-abn-acn-checksum.p.rapidapi.com"
      }
    }
  },
  "servers": [
    {
      "url": "https://australian-abn-acn-checksum.p.rapidapi.com",
      "description": "RapidAPI gateway"
    }
  ],
  "security": [
    {
      "RapidApiKey": []
    }
  ]
}