> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zapfy.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Check numbers

> Checks in a batch which numbers are on WhatsApp. For each number it indicates whether the number is on WhatsApp.



## OpenAPI

````yaml /en/api-reference/openapi.json post /contacts/check
openapi: 3.1.0
info:
  title: Zapfy API
  description: >-
    Multi-tenant WhatsApp API. Send messages and manage webhooks through a
    single surface.
  version: 1.0.0
servers:
  - url: https://api.zapfy.io/v1
security:
  - accountToken: []
paths:
  /contacts/check:
    post:
      tags:
        - Contacts
      summary: Check numbers
      description: >-
        Checks in a batch which numbers are on WhatsApp. For each number it
        indicates whether the number is on WhatsApp.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CheckContactsBody'
      responses:
        '200':
          $ref: '#/components/responses/ContactCheckList'
        '400':
          $ref: '#/components/responses/Error'
        '401':
          $ref: '#/components/responses/Error'
        '403':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
        - instanceToken: []
components:
  schemas:
    CheckContactsBody:
      type: object
      required:
        - phones
      properties:
        phones:
          type: array
          minItems: 1
          items:
            $ref: '#/components/schemas/Recipient'
          description: Phone numbers to check (E.164), in a batch.
          example:
            - '5511999998888'
    Recipient:
      type: string
      description: >-
        Recipient: a phone in E.164 (with or without `+`, spaces or formatting,
        e.g. `5511999998888` or `+55 11 99999-8888`) or a group id. To send to a
        group, use the group id (from `GET /groups`).
      example: '5511999998888'
    ContactCheckResult:
      type: object
      properties:
        phone:
          type: string
          description: Checked phone, echoed from the request.
          example: '5511999998888'
        exists:
          type: boolean
          description: Whether the number is on WhatsApp.
          example: true
  responses:
    ContactCheckList:
      description: Check result.
      content:
        application/json:
          schema:
            type: object
            properties:
              data:
                type: array
                items:
                  $ref: '#/components/schemas/ContactCheckResult'
    Error:
      description: Error.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
                example: Instance not found
  securitySchemes:
    accountToken:
      type: http
      scheme: bearer
      description: Account token (`zpfy_acct_...`) — manages instances and webhooks.
    instanceToken:
      type: http
      scheme: bearer
      description: Instance token (`zpfy_inst_...`) — sends messages.

````