> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://help.chrisp.chat/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# How to automatically set users phone numbers

__Learn how to set an authenticated visitor phone number from your website code.__

When your website already knows the visitor phone number, you can pass it to Crisp so agents have the right contact details without asking the customer to type them again.

---

# Set the visitor phone number

Use the ****$crisp JavaScript SDK**** after the Crisp chatbox snippet is available on the page.

```
// Replace this value with the phone number from your own authenticated user data.$crisp.push(["set", "user:phone", ["+14152370800"]]);
```

Use an international format when possible, such as ****E.164**** with a country code.

---

# Developer documentation

Read the [$crisp Methods documentation](https://docs.crisp.chat/guides/chatbox-sdks/web-sdk/dollar-crisp/) for more user setters, including ****email****, ****nickname****, ****avatar****, ****company****, and custom session data.