diff --git a/README.md b/README.md
index 7b20233..99e6911 100644
--- a/README.md
+++ b/README.md
@@ -31,6 +31,8 @@ applicationKey: <ovh_application_key>
 applicationSecret: <ovh_application_secret>
 consumerKey: <ovh_consumer_key>
 
+duration: <date-interval>
+
 projects:
   - id: "<project-1-id>"
     instances:
@@ -49,6 +51,15 @@ projects:
   ...
 ```
 
+#### Configure `duration`
+
+To determine after how many days/weeks/months/... you want snapshots to be delete, use `duration` option.  
+This option uses PHP `DateInterval` format : <http://php.net/manual/en/dateinterval.construct.php>
+
+The format starts with the letter P, for "period." Each duration period is represented by an integer value followed by a period designator. If the duration contains time elements, that portion of the specification is preceded by the letter T.
+
+Here are some simple examples. Two days is `P2D`. Two seconds is `PT2S`. Six years and five minutes is `P6YT5M`.
+
 ## Run
 
 `php snapshot.php`
diff --git a/snapshot.php b/snapshot.php
index ebb8fe6..b5fa4de 100644
--- a/snapshot.php
+++ b/snapshot.php
@@ -12,6 +12,25 @@
   echo '--------------------------------------------------'.PHP_EOL;
   echo 'PROJECT: '.$p['id'].PHP_EOL;
 
+  if (isset($config['duration']) && !empty($config['duration'])) {
+    $list = $ovh->get('/cloud/project/'.$p['id'].'/snapshot');
+
+    $time = new DateTime();
+    $time->sub(new DateInterval($config['duration']));
+    echo 'Delete snapshots older than '.$time->format('Y-m-d H:i:s').PHP_EOL;
+
+    $count = 0;
+    foreach ($list as $snapshot) {
+      $snapshot_time = new DateTime($snapshot['creationDate']);
+      if ($snapshot_time < $time) {
+        $ovh->delete('/cloud/project/'.$p['id'].'/snapshot/'.$snapshot['id']);
+        echo 'Delete snapshot "'.$snapshot['name'].'" ('.$snapshot_time->format('Y-m-d H:i:s').')'.PHP_EOL;
+        $count++;
+      }
+    }
+    echo sprintf('%d deleted snapshot(s)', $count).PHP_EOL;
+  }
+
   foreach ($p['instances'] as $instance) {
     $snapshot = $ovh->post('/cloud/project/'.$p['id'].'/instance/'.$instance['id'].'/snapshot', array(
       'snapshotName' => $instance['name'].' ('.date('Y-m-d H:i:s').')'