diff --git a/list_missing_hwids.py b/list_missing_hwids.py
new file mode 100644
index 0000000..d1f64ea
--- /dev/null
+++ b/list_missing_hwids.py
@@ -0,0 +1,50 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+from grmn import devices
+
+last_id = 0
+missing = []
+for i in range(0, 9999):
+    if i in devices.DEVICES:
+        last_id = i
+        continue
+    missing.append(i)
+
+print("./get_updates.py", end="")
+
+missing_count = 0
+cur_line = 0
+for i in range(0, 9999):
+    if i >= last_id:
+        break
+    if i % 10 == 0 and cur_line > 5:
+        print()
+        print("./get_updates.py", end="")
+        cur_line = 0
+    if not i in missing:
+        continue
+    if i <= last_id:
+        print(" {:04}".format(i), end="")
+        missing_count += 1
+        cur_line += 1
+
+
+print()
+print("{} unknown ids.".format(missing_count))
+print("Last known id is: {:04}".format(last_id))
+print("-" * 100)
+print("Here are some possible future ids:")
+
+print("./get_updates.py", end="")
+
+cur_line = 0
+for i in range(last_id + 1, last_id + 100):
+    if i % 10 == 0 and cur_line > 5:
+        print()
+        print("./get_updates.py", end="")
+        cur_line = 0
+    print(" {:04}".format(i), end="")
+    cur_line += 1
+
+print()