openapi: 3.2.0
info:
  title: Abstract VAT Validation Validate API
  description: 'Validate a VAT number and retrieve the registered company details, calculate VAT-compliant prices for a given amount and country, and look up the latest VAT rates and reduced-rate categories for a country. Authenticate with your API key as the `api_key` query parameter, or as an `Authorization: Bearer ` header. GET and POST (form-encoded or JSON) are both supported.'
  version: 1.0.0
  termsOfService: https://www.abstractapi.com/legal/legal
  contact:
    name: Abstract API
    url: https://www.abstractapi.com/api/vat-validation-rates-api
  license:
    name: Commercial — see Terms of Service
    url: https://www.abstractapi.com/legal/legal
servers:
- url: https://vat.abstractapi.com/v1
security:
- ApiKeyQuery: []
- BearerAuth: []
tags:
- name: Validate
paths:
  /validate:
    get:
      operationId: getValidateVat
      summary: Validate a VAT number
      description: Checks whether the submitted VAT number is valid and, if it is, returns the registered company details.
      parameters:
      - name: vat_number
        in: query
        required: true
        description: The VAT number to validate.
        schema:
          type: string
        example: SE556656688001
      responses:
        '200':
          description: Validation result for the VAT number.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/VatValidation'
              example:
                vat_number: SE556656688001
                valid: true
                company:
                  name: GOOGLE SWEDEN AB
                  address: "GOOGLE IRLAND LTD \nM COLLINS, GORDON HOUSE \nBARROW STREET, DUBLIN 4 \nIRLAND"
                country:
                  code: SE
                  name: Sweden
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '422':
          $ref: '#/components/responses/QuotaReached'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
      tags:
      - Validate
    post:
      operationId: postValidateVat
      summary: Validate a VAT number
      description: 'Same as the GET operation. The API key may be supplied in the request body, as the `api_key` query parameter, or as an `Authorization: Bearer ` header.'
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              $ref: '#/components/schemas/ValidateRequest'
          application/json:
            schema:
              $ref: '#/components/schemas/ValidateRequest'
      responses:
        '200':
          description: Validation result for the VAT number.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/VatValidation'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '422':
          $ref: '#/components/responses/QuotaReached'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
      tags:
      - Validate
components:
  responses:
    QuotaReached:
      description: Unprocessable — monthly quota reached or insufficient API credits. The body follows the standard error envelope.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    TooManyRequests:
      description: Too Many Requests — rate limit exceeded (free plans are limited to 1 request per second). The body follows the standard error envelope.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    BadRequest:
      description: Bad request — a required parameter is missing or failed validation.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              message: A validation error occurred.
              code: validation_error
              details:
                vat_number:
                - This is a required argument.
    ServerError:
      description: Internal server error. The body follows the standard error envelope.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    Unauthorized:
      description: Unauthorized — missing or invalid API key.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              message: Invalid API key provided.
              code: unauthorized
              details: null
  schemas:
    ValidateRequest:
      type: object
      required:
      - vat_number
      properties:
        vat_number:
          type: string
          description: The VAT number to validate.
          example: SE556656688001
        api_key:
          type: string
          description: 'Your API key. Optional here if supplied as the `api_key` query parameter or an `Authorization: Bearer <key>` header.'
    VatValidation:
      type: object
      properties:
        vat_number:
          type: string
          description: The VAT number that was submitted for validation.
          example: SE556656688001
        valid:
          type: boolean
          description: True if the submitted VAT number is valid.
          example: true
        company:
          type:
          - object
          - 'null'
          description: Registered company details associated with the VAT number; may be null when no company details are available.
          properties:
            name:
              type:
              - string
              - 'null'
              description: The name of the company associated with the VAT number.
            address:
              type:
              - string
              - 'null'
              description: The address of the company associated with the VAT number.
        country:
          type:
          - object
          - 'null'
          description: The country associated with the VAT number; may be null when it cannot be determined.
          properties:
            code:
              type:
              - string
              - 'null'
              description: The two-letter ISO 3166-1 alpha-2 code of the country.
            name:
              type:
              - string
              - 'null'
              description: The name of the country.
    Error:
      type: object
      required:
      - error
      properties:
        error:
          type: object
          required:
          - message
          - code
          properties:
            message:
              type: string
              description: Human-readable description of the error.
              example: A validation error occurred.
            code:
              type: string
              description: Machine-readable error code, e.g. validation_error or unauthorized.
              example: validation_error
            details:
              type:
              - object
              - 'null'
              description: Field-keyed validation messages for validation_error responses; null for other error types.
              additionalProperties:
                type: array
                items:
                  type: string
  securitySchemes:
    ApiKeyQuery:
      type: apiKey
      in: query
      name: api_key
      description: Your unique VAT Validation API key.
    BearerAuth:
      type: http
      scheme: bearer
      description: Send your API key as a Bearer token; omit `api_key` from the query string.
externalDocs:
  description: Official documentation
  url: https://docs.abstractapi.com/api/vat-validation
x-openItems:
- The exact code and message strings for the 422 (quota reached / insufficient credits), 429 (rate limit) and 500 (server error) responses are unconfirmed. The error envelope shape is modeled from the documented 400/401 examples, but the literal code and message values for these statuses are not verified against production.
- Which response fields can truly return null is assumed generously per the nullability convention and needs production confirmation. Specifically, this spec marks VatCalculation.amount_excluding_vat, amount_including_vat, vat_amount and vat_rate as nullable, and VatCategory.rate and category as nullable; these assumptions need backend confirmation.
- Whether VatValidation.company and VatValidation.country can be null on a valid VAT lookup (and which of their sub-fields can be null) is assumed and needs production confirmation.
- The calculate and categories docs label the monetary/rate fields (amount_excluding_vat, amount_including_vat, vat_amount, vat_rate, and VatCategory.rate) as Float, but the documented JSON examples return them as quoted strings (e.g. '175.00', '0.190', '0.070'). They are modeled as type:string to match the actual wire format; the Float-vs-string discrepancy needs backend confirmation.
- CORS support is unknown and needs confirmation.