diff --git a/lib/convert_api/client.rb b/lib/convert_api/client.rb
index 59489e7..e028ef4 100644
--- a/lib/convert_api/client.rb
+++ b/lib/convert_api/client.rb
@@ -101,10 +101,10 @@ def http(options = {})
     end
 
     def request_uri(path, params = {})
-      raise(SecretError, 'API secret not configured') if config.api_secret.nil?
+      raise(AuthenticationError, 'API secret or Token not configured') if authentication.nil?
 
-      params_with_secret = params.merge(Secret: config.api_secret)
-      query = URI.encode_www_form(params_with_secret)
+      params_with_authentication = params.merge(authentication)
+      query = URI.encode_www_form(params_with_authentication)
 
       base_uri.path + path + '?' + query
     end
@@ -123,6 +123,13 @@ def build_form_data(params)
       data
     end
 
+    def authentication
+      return { Token: config.token } unless config.token.nil?
+      return { Secret: config.api_secret } unless config.api_secret.nil?
+
+      nil
+    end
+
     def base_uri
       config.base_uri
     end
diff --git a/lib/convert_api/configuration.rb b/lib/convert_api/configuration.rb
index bcd43f5..8f0783c 100644
--- a/lib/convert_api/configuration.rb
+++ b/lib/convert_api/configuration.rb
@@ -1,6 +1,7 @@
 module ConvertApi
   class Configuration
     attr_accessor :api_secret
+    attr_accessor :token
     attr_accessor :base_uri
     attr_accessor :connect_timeout
     attr_accessor :read_timeout
diff --git a/lib/convert_api/errors.rb b/lib/convert_api/errors.rb
index ccff5ad..bdf78d0 100644
--- a/lib/convert_api/errors.rb
+++ b/lib/convert_api/errors.rb
@@ -1,6 +1,6 @@
 module ConvertApi
   class Error < StandardError; end
-  class SecretError < Error; end
+  class AuthenticationError < Error; end
   class FileNameError < Error; end
   class TimeoutError < Error; end
   class ConnectionFailed < Error; end
diff --git a/spec/convert_api_spec.rb b/spec/convert_api_spec.rb
index 14df27f..75ee433 100644
--- a/spec/convert_api_spec.rb
+++ b/spec/convert_api_spec.rb
@@ -10,15 +10,18 @@
 
   describe '.configure' do
     let(:api_secret) { 'test_secret' }
+    let(:token) { 'test_token' }
     let(:conversion_timeout) { 20 }
 
     it 'configures' do
       described_class.configure do |config|
         config.api_secret = api_secret
+        config.token = token
         config.conversion_timeout = conversion_timeout
       end
 
       expect(described_class.config.api_secret).to eq(api_secret)
+      expect(described_class.config.token).to eq(token)
       expect(described_class.config.conversion_timeout).to eq(conversion_timeout)
     end
   end
@@ -89,19 +92,24 @@
       it_behaves_like 'successful conversion'
     end
 
-    context 'when secret is not set' do
-      before { ConvertApi.config.api_secret = nil }
+    context 'when has error' do
+      it 'raises error without secret or token' do
+        described_class.config.api_secret = nil
+        described_class.config.token = nil
 
-      it 'raises error' do
-        expect { subject }.to raise_error(ConvertApi::SecretError, /not configured/)
+        expect { subject }.to raise_error(ConvertApi::AuthenticationError, /not configured/)
       end
-    end
 
-    context 'with invalid secret' do
-      before { ConvertApi.config.api_secret = 'invalid' }
+      it 'with invalid secret' do
+        described_class.config.api_secret = 'invalid'
 
-      it 'raises error' do
-        expect { subject }.to raise_error(ConvertApi::ClientError, /bad secret/)
+        expect { subject }.to raise_error(ConvertApi::ClientError)
+      end
+
+      it 'with invalid token' do
+        described_class.config.token = 'invalid'
+
+        expect { subject }.to raise_error(ConvertApi::ClientError)
       end
     end