diff --git a/src/app.js b/src/app.js
index d24a74a..65e63f9 100644
--- a/src/app.js
+++ b/src/app.js
@@ -1930,6 +1930,70 @@ function normalizeObsOverlaySettings(raw = {}) {
   };
 }
 
+function normalizeDriver(driver = {}) {
+  return {
+    id: String(driver?.id || uid("driver")),
+    name: String(driver?.name || "").trim(),
+    classId: String(driver?.classId || "").trim(),
+    transponder: String(driver?.transponder || "").trim(),
+    brand: String(driver?.brand || "").trim(),
+  };
+}
+
+function normalizeCar(car = {}) {
+  return {
+    id: String(car?.id || uid("car")),
+    name: String(car?.name || "").trim(),
+    transponder: String(car?.transponder || "").trim(),
+    brand: String(car?.brand || "").trim(),
+  };
+}
+
+function normalizeSession(session = {}) {
+  const type = SESSION_TYPES.includes(String(session?.type || "").toLowerCase())
+    ? String(session.type).toLowerCase()
+    : "practice";
+  const status = ["ready", "running", "stopped", "finished"].includes(String(session?.status || "").toLowerCase())
+    ? String(session.status).toLowerCase()
+    : "ready";
+  const seedMethod = ["best_sum", "average", "consecutive"].includes(String(session?.seedMethod || "").toLowerCase())
+    ? String(session.seedMethod).toLowerCase()
+    : "best_sum";
+  const assignments = Array.isArray(session?.assignments)
+    ? session.assignments
+        .map((assignment) => ({
+          id: String(assignment?.id || uid("as")),
+          driverId: String(assignment?.driverId || "").trim(),
+          carId: String(assignment?.carId || "").trim(),
+        }))
+        .filter((assignment) => assignment.driverId || assignment.carId)
+    : [];
+  return {
+    ...session,
+    id: String(session?.id || uid("session")),
+    eventId: String(session?.eventId || "").trim(),
+    name: String(session?.name || "").trim(),
+    type,
+    durationMin: Math.max(1, Number(session?.durationMin || 1) || 1),
+    followUpSec: Math.max(0, Number(session?.followUpSec || 0) || 0),
+    startMode: normalizeStartMode(session?.startMode || "mass"),
+    seedBestLapCount: Math.max(0, Number(session?.seedBestLapCount || 0) || 0),
+    seedMethod,
+    staggerGapSec: Math.max(0, Number(session?.staggerGapSec || 0) || 0),
+    maxCars: session?.maxCars ? Math.max(1, Number(session.maxCars) || 1) : null,
+    mode: session?.mode === "track" ? "track" : "race",
+    status,
+    startedAt: Number.isFinite(Number(session?.startedAt)) ? Number(session.startedAt) : null,
+    endedAt: Number.isFinite(Number(session?.endedAt)) ? Number(session.endedAt) : null,
+    finishedByTimer: session?.finishedByTimer === true,
+    assignments,
+    driverIds: Array.isArray(session?.driverIds) ? session.driverIds.map(String).filter(Boolean) : [],
+    manualGridIds: Array.isArray(session?.manualGridIds) ? session.manualGridIds.map(String).filter(Boolean) : [],
+    gridCustomized: session?.gridCustomized === true,
+    generated: session?.generated === true,
+  };
+}
+
 function parseOverlayBooleanParam(name, fallback) {
   const raw = urlParams.get(name);
   if (raw == null) {