Index: sbin/sysctl/sysctl.c
===================================================================
--- sbin/sysctl/sysctl.c
+++ sbin/sysctl/sysctl.c
@@ -81,7 +81,7 @@
 static int	sysctl_all(int *oid, int len);
 static int	name2oid(const char *, int *);
 
-static int	strIKtoi(const char *, char **);
+static int	strIKtoi(const char *, char **, const char *);
 
 static int ctl_sign[CTLTYPE+1] = {
 	[CTLTYPE_INT] = 1,
@@ -336,8 +336,8 @@
 
 		switch (kind & CTLTYPE) {
 			case CTLTYPE_INT:
-				if (strcmp(fmt, "IK") == 0)
-					intval = strIKtoi(newvalstr, &endptr);
+				if (strncmp(fmt, "IK", 2) == 0)
+					intval = strIKtoi(newvalstr, &endptr, fmt);
 				else
 					intval = (int)strtol(newvalstr, &endptr,
 					    0);
@@ -666,12 +666,13 @@
 #endif
 
 static int
-strIKtoi(const char *str, char **endptrp)
+strIKtoi(const char *str, char **endptrp, const char *fmt)
 {
 	int kelv;
 	float temp;
 	size_t len;
 	const char *p;
+	int prec, i;
 
 	assert(errno == 0);
 
@@ -679,6 +680,10 @@
 	/* caller already checked this */
 	assert(len > 0);
 
+	if (fmt[2] != '\0')
+		prec = fmt[2] - '0';
+	else
+		prec = 1;
 	p = &str[len - 1];
 	if (*p == 'C' || *p == 'F') {
 		temp = strtof(str, endptrp);
@@ -686,7 +691,10 @@
 			if (*p == 'F')
 				temp = (temp - 32) * 5 / 9;
 			*endptrp = NULL;
-			return (temp * 10 + 2732);
+			temp += 273.15;
+			for (i = 0; i < prec; i++)
+				temp *= 10.0;
+			return ((int)(temp + 0.5));
 		}
 	} else {
 		kelv = (int)strtol(str, endptrp, 10);
@@ -772,7 +780,9 @@
 	size_t intlen;
 	size_t j, len;
 	u_int kind;
+	float base;
 	int (*func)(size_t, void *);
+	int prec;
 
 	/* Silence GCC. */
 	umv = mv = intlen = 0;
@@ -893,8 +903,24 @@
 			else if (fmt[1] == 'K') {
 				if (mv < 0)
 					printf("%jd", mv);
-				else
-					printf("%.1fC", (mv - 2732.0) / 10);
+				else {
+					/*
+					 * fmt is IKx, where x is optional and
+					 * specifies the precision of the
+					 * temperature. x defaults to 1 to give
+					 * historical behavior. Many temperature
+					 * sources have precisions that exceed
+					 * their accuracy, however.
+					 */
+					prec = 1;
+					if (fmt[2] != '\0')
+						prec = fmt[2] - '0';
+					base = 1.0;
+					for (int i = 0; i < prec; i++)
+						base *= 10.0;
+					printf("%.*fC", prec,
+					    (float)mv / base - 273.15);
+				}
 			} else
 				printf(hflag ? "%'jd" : "%jd", mv);
 			sep1 = " ";
Index: share/man/man9/sysctl.9
===================================================================
--- share/man/man9/sysctl.9
+++ share/man/man9/sysctl.9
@@ -327,6 +327,13 @@
 .Dq I
 for
 .Li "int" ,
+.Dq IK
+for
+.Li "int"
+temperature in Kelvin.
+An optional single digit suffix, which defaults to 1, after
+.Dq IK
+specifies how many places to move the decimal point left,
 .Dq IU
 for
 .Li "unsigned int" ,