diff --git a/unusedid b/unusedid
new file mode 100755
index 0000000..0ae485e
--- /dev/null
+++ b/unusedid
@@ -0,0 +1,7 @@
+#!/usr/bin/python3
+
+import subprocess
+
+s = str(subprocess.check_output(['getent', 'passwd']))
+
+print([i for i in range(1000, 1100) if str(i) not in s])