diff --git a/dnsping.py b/dnsping.py
index 2e7476b..bbd5b39 100755
--- a/dnsping.py
+++ b/dnsping.py
@@ -196,7 +196,10 @@ def main():
         r_min = min(response_time)
         r_max = max(response_time)
         r_avg = sum(response_time) / r_received
-        r_stddev = stdev(response_time)
+        if len(response_time) > 1:
+            r_stddev = stdev(response_time)
+        else:
+            r_stddev = 0
     else:
         r_min = 0
         r_max = 0