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

# Check WhatsApp

> Check if phone numbers are registered on WhatsApp

Verify if one or more phone numbers have WhatsApp accounts. Use this before sending messages to avoid errors.

## Request Body

<ParamField body="phones" type="string[]" required>
  Array of phone numbers to check in international format
</ParamField>

## Response Fields

<ResponseField name="data.users" type="array">
  <Expandable title="User object">
    <ResponseField name="query" type="string">
      The phone number that was queried
    </ResponseField>

    <ResponseField name="isInWhatsapp" type="boolean">
      Whether the number has a WhatsApp account
    </ResponseField>

    <ResponseField name="jid" type="string">
      WhatsApp JID if registered, null otherwise
    </ResponseField>

    <ResponseField name="verifiedName" type="string">
      Business verified name if available
    </ResponseField>
  </Expandable>
</ResponseField>

<RequestExample>
  ```bash cURL theme={null}
  curl -X POST https://api.livchat.ai/v1/contacts/check \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "phones": ["5511999999999", "5511888888888"]
    }'
  ```

  ```javascript JavaScript theme={null}
  const response = await fetch("https://api.livchat.ai/v1/contacts/check", {
    method: "POST",
    headers: {
      Authorization: "Bearer YOUR_API_KEY",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      phones: ["5511999999999", "5511888888888"],
    }),
  });

  const { data } = await response.json();

  // Filter valid numbers
  const validNumbers = data.users.filter(u => u.isInWhatsapp);
  ```

  ```python Python theme={null}
  import requests

  response = requests.post(
      "https://api.livchat.ai/v1/contacts/check",
      headers={
          "Authorization": "Bearer YOUR_API_KEY",
          "Content-Type": "application/json",
      },
      json={
          "phones": ["5511999999999", "5511888888888"],
      },
  )

  data = response.json()
  valid_numbers = [u for u in data["data"]["users"] if u["isInWhatsapp"]]
  ```
</RequestExample>

<ResponseExample>
  ```json 200 theme={null}
  {
    "success": true,
    "code": 200,
    "data": {
      "users": [
        {
          "query": "5511999999999",
          "isInWhatsapp": true,
          "jid": "5511999999999@s.whatsapp.net",
          "verifiedName": "Company Name"
        },
        {
          "query": "5511888888888",
          "isInWhatsapp": false,
          "jid": null,
          "verifiedName": ""
        }
      ]
    }
  }
  ```
</ResponseExample>

<Note>
  Checking numbers before sending helps you avoid errors and saves API calls.
</Note>