diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c
--- a/sbin/ping/ping.c
+++ b/sbin/ping/ping.c
@@ -1522,10 +1522,10 @@
 	if (nreceived && timing) {
 		double n = nreceived + nrepeats;
 		double avg = tsum / n;
-		double vari = tsumsq / n - avg * avg;
+		double stddev = sqrt(fmax(0, tsumsq / n - avg * avg));
 		(void)printf(
 		    "round-trip min/avg/max/stddev = %.3f/%.3f/%.3f/%.3f ms\n",
-		    tmin, avg, tmax, sqrt(vari));
+		    tmin, avg, tmax, stddev);
 	}
 
 	if (nreceived)
diff --git a/sbin/ping/ping6.c b/sbin/ping/ping6.c
--- a/sbin/ping/ping6.c
+++ b/sbin/ping/ping6.c
@@ -2349,10 +2349,10 @@
 		/* Only display average to microseconds */
 		double num = nreceived + nrepeats;
 		double avg = tsum / num;
-		double dev = sqrt(tsumsq / num - avg * avg);
+		double stddev = sqrt(fmax(0, tsumsq / num - avg * avg));
 		(void)printf(
 		    "round-trip min/avg/max/std-dev = %.3f/%.3f/%.3f/%.3f ms\n",
-		    tmin, avg, tmax, dev);
+		    tmin, avg, tmax, stddev);
 		(void)fflush(stdout);
 	}
 	(void)fflush(stdout);