diff --git a/README.md b/README.md
index 5aa4ab2..3059a78 100644
--- a/README.md
+++ b/README.md
@@ -44,12 +44,12 @@ If you use Composer, these dependencies should be handled automatically. If you
 
 ### Configuration
 
-You can get your secret at https://www.convertapi.com/a
+You can get your API credentials at https://www.convertapi.com/a
 
 ```php
 use \ConvertApi\ConvertApi;
 
-ConvertApi::setApiSecret('your-api-secret');
+ConvertApi::setApiCredentials('your-api-secret-or-token');
 ```
 
 ### File conversion
diff --git a/examples/conversions_chaining.php b/examples/conversions_chaining.php
index de4593f..8bbebf4 100644
--- a/examples/conversions_chaining.php
+++ b/examples/conversions_chaining.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Short example of conversions chaining, the PDF pages extracted and saved as separated JPGs and then ZIP'ed
 # https://www.convertapi.com/doc/chaining
diff --git a/examples/convert_stream.php b/examples/convert_stream.php
index 227b7d9..c3e0481 100644
--- a/examples/convert_stream.php
+++ b/examples/convert_stream.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Example of converting content stream to PDF
 # https://www.convertapi.com/txt-to-pdf
diff --git a/examples/convert_url_to_pdf.php b/examples/convert_url_to_pdf.php
index 34c9ff0..aa06962 100644
--- a/examples/convert_url_to_pdf.php
+++ b/examples/convert_url_to_pdf.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Example of converting Web Page URL to PDF file
 # https://www.convertapi.com/web-to-pdf
diff --git a/examples/convert_word_to_pdf_and_png.php b/examples/convert_word_to_pdf_and_png.php
index 1ce2ed3..3c83ac8 100644
--- a/examples/convert_word_to_pdf_and_png.php
+++ b/examples/convert_word_to_pdf_and_png.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Example of saving Word docx to PDF and to PNG
 # https://www.convertapi.com/docx-to-pdf
diff --git a/examples/create_pdf_thumbnail.php b/examples/create_pdf_thumbnail.php
index a111eb5..4cd271e 100644
--- a/examples/create_pdf_thumbnail.php
+++ b/examples/create_pdf_thumbnail.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Example of extracting first page from PDF and then chaining conversion PDF page to JPG.
 # https://www.convertapi.com/pdf-to-extract
diff --git a/examples/error_handling.php b/examples/error_handling.php
index ae0f0c9..16dcf06 100644
--- a/examples/error_handling.php
+++ b/examples/error_handling.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 try {
     $result = ConvertApi::convert('svg', ['File' => 'files/test.docx']);
diff --git a/examples/retrieve_user_information.php b/examples/retrieve_user_information.php
index 77d0d50..d8db60c 100644
--- a/examples/retrieve_user_information.php
+++ b/examples/retrieve_user_information.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Retrieve user information
 # https://www.convertapi.com/doc/user
diff --git a/examples/split_and_merge_pdf.php b/examples/split_and_merge_pdf.php
index a8a20b1..69171cf 100644
--- a/examples/split_and_merge_pdf.php
+++ b/examples/split_and_merge_pdf.php
@@ -3,8 +3,8 @@
 
 use \ConvertApi\ConvertApi;
 
-# set your api secret
-ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+# set your api secret or token
+ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
 
 # Example of extracting first and last pages from PDF and then merging them back to new PDF.
 # https://www.convertapi.com/pdf-to-split
diff --git a/lib/ConvertApi/Client.php b/lib/ConvertApi/Client.php
index 64e2caf..0ec1c42 100644
--- a/lib/ConvertApi/Client.php
+++ b/lib/ConvertApi/Client.php
@@ -169,12 +169,15 @@ private function parseResponse($response)
 
     private function url($path)
     {
-        return ConvertApi::$apiBase . $path . '?secret=' . ConvertApi::getApiSecret();
+        return ConvertApi::$apiBase . $path;
     }
 
     private function defaultHeaders()
     {
-        return ['Accept: application/json'];
+        return [
+            'Accept: application/json',
+            'Authorization: Bearer ' . ConvertApi::getApiCredentials(),
+        ];
     }
 
     private function userAgent()
diff --git a/lib/ConvertApi/ConvertApi.php b/lib/ConvertApi/ConvertApi.php
index 0b0547c..fed6c0b 100644
--- a/lib/ConvertApi/ConvertApi.php
+++ b/lib/ConvertApi/ConvertApi.php
@@ -12,8 +12,8 @@ class ConvertApi
     // ConvertAPI client version.
     const VERSION = '2.0.1';
 
-    // @var string The Convert API secret. You can get your secret at https://www.convertapi.com/a
-    public static $apiSecret;
+    // @var string The Convert API credentials. You can get your credentials at https://www.convertapi.com/a
+    public static $apiCredentials;
 
     // @var string The base URL for the Convert API
     public static $apiBase = 'https://v2.convertapi.com/';
@@ -40,21 +40,21 @@ class ConvertApi
     private static $_client;
 
     /**
-     * @return string The API secret used for requests.
+     * @return string The API credentials used for requests.
      */
-    public static function getApiSecret()
+    public static function getApiCredentials()
     {
-        return self::$apiSecret;
+        return self::$apiCredentials;
     }
 
     /**
-     * Sets API secret used for requests.
+     * Sets API secret or token used for requests.
      *
-     * @param string $apiSecret
+     * @param string $apiCredentials
      */
-    public static function setApiSecret($apiSecret)
+    public static function setApiCredentials($apiCredentials)
     {
-        self::$apiSecret = $apiSecret;
+        self::$apiCredentials = $apiCredentials;
     }
 
     /**
diff --git a/tests/ConvertApi/ConvertApiTest.php b/tests/ConvertApi/ConvertApiTest.php
index cc71731..31f3810 100644
--- a/tests/ConvertApi/ConvertApiTest.php
+++ b/tests/ConvertApi/ConvertApiTest.php
@@ -11,25 +11,25 @@ class ConvertApiTest extends \PHPUnit\Framework\TestCase
     protected function setUp(): void
     {
         // Save original values so that we can restore them after running tests
-        $this->origApiSecret = ConvertApi::getApiSecret();
+        $this->origApiCredentials = ConvertApi::getApiCredentials();
         $this->origApiBase = ConvertApi::getApiBase();
         $this->origUploadTimeout = ConvertApi::$uploadTimeout;
 
-        ConvertApi::setApiSecret(getenv('CONVERT_API_SECRET'));
+        ConvertApi::setApiCredentials(getenv('CONVERT_API_SECRET'));
     }
 
     protected function tearDown(): void
     {
         // Restore original values
-        ConvertApi::setApiSecret($this->origApiSecret);
+        ConvertApi::setApiCredentials($this->origApiCredentials);
         ConvertApi::setApiBase($this->origApiBase);
         ConvertApi::$uploadTimeout = $this->origUploadTimeout;
     }
 
     public function testConfigurationAccessors()
     {
-        ConvertApi::setApiSecret('test-secret');
-        $this->assertEquals('test-secret', ConvertApi::getApiSecret());
+        ConvertApi::setApiCredentials('test-secret');
+        $this->assertEquals('test-secret', ConvertApi::getApiCredentials());
 
         ConvertApi::setApiBase('https://foo.bar');
         $this->assertEquals('https://foo.bar', ConvertApi::getApiBase());