diff --git a/index.d.ts b/index.d.ts
index bdd7f54..70e7d99 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -615,6 +615,8 @@ declare namespace WAWebJS {
         hasMedia: boolean,
         /** Indicates if the message was sent as a reply to another message */
         hasQuotedMsg: boolean,
+        /** Indicates the duration of the message in seconds */
+        duration: string,
         /** ID that represents the message */
         id: MessageId,
         /** Indicates if the message was forwarded */
diff --git a/src/structures/Message.js b/src/structures/Message.js
index 6a326b9..ea541fa 100644
--- a/src/structures/Message.js
+++ b/src/structures/Message.js
@@ -134,6 +134,12 @@ class Message extends Base {
          */
         this.hasQuotedMsg = data.quotedMsg ? true : false;
 
+        /**
+         * Indicates the duration of the message in seconds
+         * @type {string}
+         */
+        this.duration = data.duration ? data.duration : undefined;
+
         /**
          * Location information contained in the message, if the message is type "location"
          * @type {Location}