diff --git a/db.py b/db.py
index 9791c67..3e60cd2 100644
--- a/db.py
+++ b/db.py
@@ -182,7 +182,7 @@ def get_active_events(limit: int = 200, offset: int = 0) -> list:
             for r in rows:
                 for k in ('first_seen', 'last_seen'):
                     if r.get(k) and hasattr(r[k], 'isoformat'):
-                        r[k] = r[k].isoformat()
+                        r[k] = r[k].isoformat() + 'Z'
             return rows
 
 
@@ -210,7 +210,7 @@ def get_recent_resolved(hours: int = 24, limit: int = 50) -> list:
             for r in rows:
                 for k in ('first_seen', 'last_seen', 'resolved_at'):
                     if r.get(k) and hasattr(r[k], 'isoformat'):
-                        r[k] = r[k].isoformat()
+                        r[k] = r[k].isoformat() + 'Z'
             return rows
 
 
@@ -252,7 +252,7 @@ def get_active_suppressions() -> list:
             for r in rows:
                 for k in ('created_at', 'expires_at'):
                     if r.get(k) and hasattr(r[k], 'isoformat'):
-                        r[k] = r[k].isoformat()
+                        r[k] = r[k].isoformat() + 'Z'
             return rows
 
 
@@ -267,7 +267,7 @@ def get_suppression_history(limit: int = 50) -> list:
             for r in rows:
                 for k in ('created_at', 'expires_at'):
                     if r.get(k) and hasattr(r[k], 'isoformat'):
-                        r[k] = r[k].isoformat()
+                        r[k] = r[k].isoformat() + 'Z'
             return rows
 
 
diff --git a/monitor.py b/monitor.py
index 445912d..d0c5463 100644
--- a/monitor.py
+++ b/monitor.py
@@ -918,7 +918,7 @@ class NetworkMonitor:
         return {
             'hosts': hosts,
             'unifi': display_unifi,
-            'updated': datetime.utcnow().isoformat(),
+            'updated': datetime.utcnow().isoformat() + 'Z',
         }
 
     # ------------------------------------------------------------------