diff --git a/index.html b/index.html
index 8595578..9af70f8 100644
--- a/index.html
+++ b/index.html
@@ -59,7 +59,19 @@
       const nameInput = document.getElementById("nameInput");
       const addButton = document.getElementById("addButton");
       const resultsTable = document.getElementById("resultsTable");
-      
+      const startAllButton = document.getElementById("startAllButton");
+
+      startAllButton.addEventListener("click", () => {
+        Object.keys(players).forEach((id) => {
+          if (players[id].length === 0) {
+            players[id].push(Date.now());
+          }
+        });
+        setCookies(players);
+        renderPlayers();
+        reloadResultsTable();
+      });
+
       const getCookies = () => {
         const cookies = document.cookie.split("; ").reduce((acc, cookie) => {
           const [key, value] = cookie.split("=");
@@ -214,6 +226,12 @@
   </button>
 </div>
 
+<div class="mt-4">
+  <button id="startAllButton" class="bg-blue-500 text-white px-4 py-2 rounded hover:bg-blue-600">
+    Lancer tous les chronos
+  </button>
+</div>
+
 
 <script>
   const exportToCSV = () => {