diff --git a/types/video.js/index.d.ts b/types/video.js/index.d.ts
index 67d2ef6dda..caaf075b7e 100644
--- a/types/video.js/index.d.ts
+++ b/types/video.js/index.d.ts
@@ -4307,7 +4307,7 @@ declare namespace videojs {
 		 *
 		 * @return The current playback rate when getting or 1.0
 		 */
-		playbackRate(rate?: number): void;
+		playbackRate(rate: number): void;
 
 		playbackRate(): number;