diff --git a/runall.py b/runall.py
index 9d19ae1..31069ca 100644
--- a/runall.py
+++ b/runall.py
@@ -21,7 +21,8 @@ def check_pairs(script, pairs):
 
 def find_script(pairs, max_length):
     candidates = []
-    total_options = len(string.printable) ** max_length
+    chars = len(string.printable)
+    total_options = int((chars ** (max_length + 1) - 1) / (chars - 1))
     current_option = 0
 
     for length in range(max_length + 1):