# How do I generate a valid SDK signature from PHP?

**URL:** <https://devforum.zoom.us/t/how-do-i-generate-a-valid-sdk-signature-from-php/70691>\
**Category:** Meetings\
**Tags:** web-meeting-sdk\
**Created:** [June 17, 2022, 2:12pm UTC](https://devforum.zoom.us/t/how-do-i-generate-a-valid-sdk-signature-from-php/70691 "2022-06-17T14:12:05Z")\
**Posts on this page:** 1\
**Showing post:** 5

<div class="post-metadata">

**Author:** ![donte.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/donte.zoom/32/24412_2.png) [@donte.zoom](https://devforum.zoom.us/u/donte.zoom)\
**Post date:** [October 18, 2022, 11:25am UTC](https://devforum.zoom.us/t/how-do-i-generate-a-valid-sdk-signature-from-php/70691/5 "2022-10-18T11:25:55Z")

</div>

@SVIF Here is example SDK Signature in PHP:

```auto

<?php

/**
 * Below are the fields required for the JWT payload

 * sdkKey: Your SDK Key. Required for Web, optional for Native.
 * sdkSecret Required, your SDK API Secret
 * mn: The Zoom Meeting or Webinar Number. Required for Web, optional for Native.
 * role: The user role. Required for Web, optional for Native. Values: 0 to specify participant, 1 to specify host.
 * iat: The current timestamp in epoch format. Required.
 * exp: JWT expiration date. Required. Values: Min = 1800 seconds greater than iat value, max = 48 hours greater than iat value. In epoch format.
 * tokenExp: JWT expiration date. Required. Values: Min = 1800 seconds greater than iat value, max = 48 hours greater than iat value. In epoch format.
 * 
 * Source: https://marketplace.zoom.us/docs/sdk/native-sdks/auth/
 */
function generateSignature($sdkKey, $sdkSecret, $meetingNumber, $role) {
    $iat = time();
    $exp = $iat + 60 * 60 * 2;
    $token_payload = [
    
        'sdkKey' => $sdkKey,
        'mn' => $meetingNumber,
        'role' => $role,
        'iat' => $iat,
        'exp' => $exp,
        'tokenExp' => $exp
    ];

    $jwt = JWT::encode($token_payload, $sdkSecret, 'HS256');
    
    return $jwt;
}

echo(generateSignature($_ENV['SDK_KEY'], $_ENV['SDK_SECRET'], 12345678912, 0));

```

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