diff --git a/usr.bin/systat/vmstat.c b/usr.bin/systat/vmstat.c
index a4a9269edb3f..bced789e4451 100644
--- a/usr.bin/systat/vmstat.c
+++ b/usr.bin/systat/vmstat.c
@@ -472,7 +472,7 @@ showkre()
 	putfloat(avenrun[1], STATROW, STATCOL + 23, 6, 2, 0);
 	putfloat(avenrun[2], STATROW, STATCOL + 29, 6, 2, 0);
 	mvaddstr(STATROW, STATCOL + 53, buf);
-#define pgtokb(pg)	((pg) * s.v_page_size / 1024)
+#define pgtokb(pg)	((pg) * (s.v_page_size / 1024))
 	putint(pgtokb(total.t_arm), MEMROW + 2, MEMCOL + 3, 8);
 	putint(pgtokb(total.t_armshr), MEMROW + 2, MEMCOL + 11, 8);
 	putint(pgtokb(total.t_avm), MEMROW + 2, MEMCOL + 19, 9);
diff --git a/usr.bin/vmstat/vmstat.c b/usr.bin/vmstat/vmstat.c
index 1bea1c5adbed..bee2ffb43895 100644
--- a/usr.bin/vmstat/vmstat.c
+++ b/usr.bin/vmstat/vmstat.c
@@ -588,7 +588,7 @@ dovmstat(unsigned int interval, int reps)
 		fill_vmtotal(&total);
 		(void)printf("%2d %1d %1d",
 		    total.t_rq - 1, total.t_dw + total.t_pw, total.t_sw);
-#define vmstat_pgtok(a) ((a) * sum.v_page_size >> 10)
+#define vmstat_pgtok(a) ((a) * (sum.v_page_size >> 10))
 #define	rate(x)	(((x) + halfuptime) / uptime)	/* round */
 		(void)printf(" %7ld %6ld ", (long)vmstat_pgtok(total.t_avm),
 			     (long)vmstat_pgtok(total.t_free));