diff --git a/cli/ops/websocket.rs b/cli/ops/websocket.rs
index 77b2b5f11d..c8fb895431 100644
--- a/cli/ops/websocket.rs
+++ b/cli/ops/websocket.rs
@@ -99,6 +99,9 @@ pub async fn op_ws_create(
   let uri: Uri = args.url.parse()?;
   let mut request = Request::builder().method(Method::GET).uri(&uri);
 
+  request =
+    request.header("User-Agent", format!("Deno/{}", crate::version::DENO));
+
   if !args.protocols.is_empty() {
     request = request.header("Sec-WebSocket-Protocol", args.protocols);
   }