How to send SMS for free using PHP? [closed]

I used to use Google Calendar , but always for the same number, I used it for a while for the alerts system.

If you really need to send SMS from your system, there are two alternatives, both paid:

1) Use a messaging service that will charge you per message. There are several, in Brazil I know only zenvia.com.br (it is not marketing, I have no relation with the brand).

• In this case, you would integrate with the company's system and send messages via the Internet (API). They have multi-system modules, and well-documented, multi-language ready libraries.

2) Use a modem attached to the server

• Only solution when there is a local server, I use and it comes out very cheap. Using a 3G modem, to install on Linux is usually complex. After all configured, I call via CLI, using

  echo '$mensagem' | sudo gammu sendsms TEXT $numero -unicode
  

To send SMS via code what happens basically is that you use an API from some carrier that when sending your request to the same it will trigger a mobile device that will send your SMS.

I do not know of any such free national service, just pay for just contacting a carrier of your choice that they will release a documentation to get you started using (paying the clear cost).

If you want international services you can find some free ones, just ask our friend google.