If you are trying to use, or already use some API, stop, this is CRIME!

There is no official API to send or receive a WhatsApp message to no language , at least until the current time of this response.

You can find something that is not official, but the guarantee that will work the first time and stay running is something unanswered, because WhatsApp will work hard to block any third parties .

You can read more about WhatsApp policy and get your questions answered.

Just one caveat, a comment from development leader Brian Acton himself at the F8 Facebook conference, translated:

  

... we do not have plans to open WhatsApp at this time ... We do not want to bother our users with messages they do not want to receive 1 ...

For this comment you probably do not have an API available for a long time.

Addendum

As stated in the comment itself, you can see that there is no possibility (so far) of an API with constant functionality:

  

After Whatsapp implemented end-to-end encryption, the "third-party" APIs stopped working. You should also check that if you send many messages in a short time Whatsapp will block as SPAM.

And in the terms of use website , translated it says:

  You must not (or assist others) access, use, copy, adapt, modify, prepare derivative works based on, distribute, license, sublicense, transfer, display, perform or otherwise otherwise exploit our Services inadmissible or unauthorized, or in ways that occupy us, harm us or harm us, our services, systems, users or others, including that you should not directly or through automated means:

     

• (A) reverse engineer, change, modify, create derivative works, decompile or extract code from our services;
  
• (B) send, store or transmit viruses or other harmful computer code through or through our Services;
  
• (C) obtain or attempt to gain unauthorized access to our Services or systems;
  
• (D) interfering with or disrupting the integrity or performance of our Services;
  
• (E) create accounts for our Services through unauthorized or automated means;
  
• (F) collect information about or about our users in an inadmissible or unauthorized way;
  
• (G) sell, resell, rent or charge for our Services;
  
• (H) distribute or make available our Services over a network where they can be used by multiple devices at the same time.
  

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