What is spoof caller id or Caller ID Spoofing ?
Caller ID spoofing is the act of making the telephone network display any desired ( Fake ) incoming number on the recipients caller ID . Have you ever wondered to know how to perform this ? or how hackers call from any number ? Well , read on to discover more information on How to spoof caller ID.

How to Spoof caller ID ?
You can easily spoof any caller ID using service like Spoofcard or the most famous Crazycall  .
Once you have completed the setup you just need to place a call. While in crazy call you have to call them and enter the pin. Here , International charges may apply depending on your plans . So activate international calling plans.

How caller ID Spoofing works ?
Caller ID Spoofing is done through various methods and using different technologies . The most commonly used technology to spoof caller ID is VOIP ( voice over IP ) or PRI ( Primary Rate Interface ) Lines .
Today , Most VOIP system provide an option for its users to enter whatever number they want in the calling party field and this number is sent out when they make a call.
Caller ID spoofing is possible and being performed right from the days caller ID system was introduced but still common people dont know this fact.

Here 1 Video TUT For it ! :)

Source :  LearnHacking