diff --git a/encoding/json/number.go b/encoding/json/number.go
index 936ba86..04f2969 100644
--- a/encoding/json/number.go
+++ b/encoding/json/number.go
@@ -12,3 +12,7 @@ func NumberToInt(n json.Number) (int, error) {
 	}
 	return int(n64), nil
 }
+
+func NumberToInt64(n json.Number) (int64, error) {
+	return strconv.ParseInt(n.String(), 10, 64)
+}