title: How to Calculate Rest API Payload Size?
body: <p>I am implementing a REST Web service API in my PHP coding, the web service have the payload size limitation of 200kb.  How can i able to calculate post json data size or payload of json data size.
  So, i exactly need to calculate the payload size, i am using json data for post type.</p>
  
  <p>example coding:  @curl_setopt($chaccess, CURLOPT_POST, true);
   @curl_setopt($chaccess, CURLOPT_POSTFIELDS, $post_json);</p>