diff --git a/format.c b/format.c
index db769668..9e671428 100644
--- a/format.c
+++ b/format.c
@@ -90,6 +90,9 @@ format_job_cmp(struct format_job *fj1, struct format_job *fj2)
 /* Maimum repeat size. */
 #define FORMAT_MAX_REPEAT 10000
 
+/* Maimum precision. */
+#define FORMAT_MAX_PRECISION 100
+
 /* Format modifiers. */
 #define FORMAT_TIMESTRING 0x1
 #define FORMAT_BASENAME 0x2
@@ -4850,7 +4853,8 @@ format_replace_expression(struct format_modifier *mexp,
 
 	/* The third argument may be precision. */
 	if (argc >= 3) {
-		prec = strtonum(mexp->argv[2], INT_MIN + 1, INT_MAX, &errstr);
+		prec = strtonum(mexp->argv[2], -FORMAT_MAX_PRECISION,
+		    FORMAT_MAX_PRECISION, &errstr);
 		if (errstr != NULL) {
 			format_log(es, "expression precision %s: %s", errstr,
 			    mexp->argv[2]);