diff --git a/DependencyInjection/Configuration.php b/DependencyInjection/Configuration.php
index b9a2bab..21a73c8 100644
--- a/DependencyInjection/Configuration.php
+++ b/DependencyInjection/Configuration.php
@@ -28,9 +28,18 @@ class Configuration implements ConfigurationInterface
                     ->children()
                         ->scalarNode('enabled')->defaultTrue()->end()
                         ->scalarNode('endpoint')->defaultValue('/app_dev.php')->end()
-                        ->enumNode('request_format_method')
-                            ->values(array('format_param', 'accept_header'))
-                            ->defaultValue('format_param')
+                        ->arrayNode('request_format')
+                            ->addDefaultsIfNotSet()
+                            ->children()
+                                ->enumNode('method')
+                                    ->values(array('format_param', 'accept_header'))
+                                    ->defaultValue('format_param')
+                                ->end()
+                                ->enumNode('default_format')
+                                    ->values(array('json', 'xml'))
+                                    ->defaultValue('json')
+                                ->end()
+                            ->end()
                         ->end()
                         ->arrayNode('authentication')
                             ->children()
diff --git a/DependencyInjection/NelmioApiDocExtension.php b/DependencyInjection/NelmioApiDocExtension.php
index 501a00e..db4867d 100644
--- a/DependencyInjection/NelmioApiDocExtension.php
+++ b/DependencyInjection/NelmioApiDocExtension.php
@@ -31,7 +31,8 @@ class NelmioApiDocExtension extends Extension
         $container->setParameter('nelmio_api_doc.api_name', $config['name']);
         $container->setParameter('nelmio_api_doc.sandbox.enabled',  $config['sandbox']['enabled']);
         $container->setParameter('nelmio_api_doc.sandbox.endpoint', $config['sandbox']['endpoint']);
-        $container->setParameter('nelmio_api_doc.sandbox.request_format_method', $config['sandbox']['request_format_method']);
+        $container->setParameter('nelmio_api_doc.sandbox.request_format.method', $config['sandbox']['request_format']['method']);
+        $container->setParameter('nelmio_api_doc.sandbox.request_format.default_format', $config['sandbox']['request_format']['default_format']);
 
         $loader = new XmlFileLoader($container, new FileLocator(__DIR__.'/../Resources/config'));
         $loader->load('formatters.xml');
diff --git a/Formatter/HtmlFormatter.php b/Formatter/HtmlFormatter.php
index 06dde5a..2981ca1 100644
--- a/Formatter/HtmlFormatter.php
+++ b/Formatter/HtmlFormatter.php
@@ -45,6 +45,11 @@ class HtmlFormatter extends AbstractFormatter
      */
     private $requestFormatMethod;
 
+    /**
+     * @var string
+     */
+    private $defaultRequestFormat;
+
     /**
      * @param array $authentication
      */
@@ -93,6 +98,11 @@ class HtmlFormatter extends AbstractFormatter
         $this->requestFormatMethod = $method;
     }
 
+    public function setDefaultRequestFormat($format)
+    {
+        $this->defaultRequestFormat = $format;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -146,14 +156,15 @@ class HtmlFormatter extends AbstractFormatter
     private function getGlobalVars()
     {
         return array(
-            'apiName'             => $this->apiName,
-            'authentication'      => $this->authentication,
-            'endpoint'            => $this->endpoint,
-            'enableSandbox'       => $this->enableSandbox,
-            'requestFormatMethod' => $this->requestFormatMethod,
-            'date'                => date(DATE_RFC822),
-            'css'                 => file_get_contents(__DIR__ . '/../Resources/public/css/screen.css'),
-            'js'                  => file_get_contents(__DIR__ . '/../Resources/public/js/all.js'),
+            'apiName'              => $this->apiName,
+            'authentication'       => $this->authentication,
+            'endpoint'             => $this->endpoint,
+            'enableSandbox'        => $this->enableSandbox,
+            'requestFormatMethod'  => $this->requestFormatMethod,
+            'defaultRequestFormat' => $this->defaultRequestFormat,
+            'date'                 => date(DATE_RFC822),
+            'css'                  => file_get_contents(__DIR__ . '/../Resources/public/css/screen.css'),
+            'js'                   => file_get_contents(__DIR__ . '/../Resources/public/js/all.js'),
         );
     }
 
diff --git a/Resources/config/formatters.xml b/Resources/config/formatters.xml
index 888268b..6a8ae76 100644
--- a/Resources/config/formatters.xml
+++ b/Resources/config/formatters.xml
@@ -38,7 +38,10 @@
                 <argument>%nelmio_api_doc.sandbox.endpoint%</argument>
             </call>
             <call method="setRequestFormatMethod">
-                <argument>%nelmio_api_doc.sandbox.request_format_method%</argument>
+                <argument>%nelmio_api_doc.sandbox.request_format.method%</argument>
+            </call>
+            <call method="setDefaultRequestFormat">
+                <argument>%nelmio_api_doc.sandbox.request_format.default_format%</argument>
             </call>
             <call method="setAuthentication">
                 <argument>%nelmio_api_doc.sandbox.authentication%</argument>
diff --git a/Resources/views/layout.html.twig b/Resources/views/layout.html.twig
index ff773fa..f314231 100644
--- a/Resources/views/layout.html.twig
+++ b/Resources/views/layout.html.twig
@@ -18,8 +18,8 @@
             <div id="sandbox_configuration">
                 request format:
                 <select id="request_format">
-                    <option value="json">JSON</option>
-                    <option value="xml">XML</option>
+                    <option value="json"{{ defaultRequestFormat == 'json' ? ' selected' : '' }}>JSON</option>
+                    <option value="xml"{{ defaultRequestFormat == 'xml' ? ' selected' : '' }}>XML</option>
                 </select>
                 {% if authentication %}
                     api key: <input type="text" id="api_key"/>