diff --git a/src/public/index.html b/src/public/index.html
index 6faf2f5..9cc6d63 100644
--- a/src/public/index.html
+++ b/src/public/index.html
@@ -99,15 +99,20 @@
                     for (var i = 0; i < voiceEles.length; i++)
                         if (voiceEles[i].checked)
                             voiceIdx = voiceEles[i].value;
-
-                    ws.send(JSON.stringify({
+                    
+                    const data = JSON.stringify({
                         "Text": input.value,
                         "Pitch": Number.parseInt(document.getElementById("pitch").value, 10),
                         "Rate": Number.parseFloat(document.getElementById("rate").value, 10),
                         "VoiceIdx": Number.parseInt(voiceIdx, 10),
-                    }));
+                    });
+
+                    ws.send(data);
                     print("SENT: " + input.value);
                     input.value = "";
+                    if (document.getElementById("listen").checked) {
+                        ws.onmessage({data: data});
+                    }
                     return false;
                 };
             });
@@ -129,6 +134,9 @@
 
                     <input id="rate" type="number" value="0"/>
                     <label for="rate">rate</label></br>
+
+                    <input id="listen" type="checkbox" />
+                    <label for="listen">listen</label></br>
                 </div>
             </div>
             <div id="output" style="flex-grow: 1; overflow-y: scroll;"></div>