Make a call with PHP

You can quickly see how the Voice API works by calling yourself using the API.

In this guide you will learn:

How to create your PHP application.
How to call your phone number.

What you need to know before you start

Before you can get started, you need the following already set up:

Set all Voice API configuration settings.
PHP 8.1 or later and a familiarity with how to create a new file.

Create your PHP file

Create a new file named make-call.php and paste the provided "make-call.php" code into the file.

Note:

This tutorial uses basic authentication for testing purposes. We recommend using a signed request for authentication in a production environment. You can follow the steps in this guide, but use the code samples from here to use request signing authentication instead.

make-call.php

Use this code to make a phone call using the Voice API.

<?php
// Requires libcurl

const key = "YOUR_key";
const secret = "YOUR_secret";
const to = "YOUR_to_number";
const fromNumber = "YOUR_from_number";
const locale = "YOUR_locale";

$payload = [
  "method" => "ttsCallout",
  "ttsCallout" => [
    "cli" => fromNumber,
    "destination" => [
      "type" => "number",
      "endpoint" => to
    ],
    "locale" => locale,
    "text" => "Hello, this is a call from Sinch. Congratulations! You made your first call."
  ]
];

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "Authorization: Basic " . base64_encode(key . ":" . secret)
  ],
  CURLOPT_POSTFIELDS => json_encode($payload),
  CURLOPT_URL => "https://calling.api.sinch.com/calling/v1/callouts",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_CUSTOMREQUEST => "POST",
]);

$response = curl_exec($curl);
$error = curl_error($curl);

curl_close($curl);

if ($error) {
  echo "cURL Error #:" . $error;
} else {
  echo $response;
}

?>

This code makes a POST request to the Voice API /callouts endpoint which then makes a call out to the to parameter in the body of the request. The Voice API uses callouts to make voice calls. In this guide, we are using the ttsCallout or "text-to-speech callout" to call a number and then play a text-to-speech message before hanging up.

To

In this example you want to call a phone number. Change the value of the to parameter to the phone number you verified in your dashboard in E.164 format.

Note:

When your account is in trial mode, you can only call your verified numbers. If you want to call any number, you need to upgrade your account!

Fill in your parameters

Before you can run the code, you need to update some values so you can connect to your Sinch account. Update the following parameters with your own values:

Parameter	Your value
`key`	The application key found on your Sinch dashboard.
`secret`	The application secret found on your Sinch dashboard.
`fromNumber`	Any number you've assigned to your application. This can be a number you've purchased or your free test number. Find the number on your Sinch dashboard by clicking on your app, navigating to the Voice and Video tab, and looking in the Inbound Numbers section.
`locale`	The language and locale you want to use for the text-to-speech call. Locale is specified with a language code according to `ISO 639`, a dash and a country code according to `ISO 3166-1 alpha-2`. For example, American English is represented by `en-US`.

Save the file.

Make your first call

Now you can execute the code and make your text-to-speech call. Run the following command:

Copy

Copied

php make-call.php

You should receive a phone call to the number you called with the message "Hello, this is a call from Sinch. Congratulations! You made your first call."

Tip:

If the text-to-speech message starts playing too early for your needs, you can use SSML to add a pause at the beginning of the message.

Troubleshooting tip

If after running your app you receive a 5000 error response, you may have forgotten to save your file after adding your authentication values. This is an easy mistake to make! Try saving the file and running the app again.

Next steps

Now that you know how to make a call, learn how to handle an incoming call.

Additional resources

API specification