diff --git a/src/app/util/util.ts b/src/app/util/util.ts
index ba2777eab67d938bb4dea7371cdaeac7d59f14fd..06db46788e2d96870913a5efd1faf8c49db487dd 100644
--- a/src/app/util/util.ts
+++ b/src/app/util/util.ts
@@ -13,7 +13,7 @@ export function logObject(obj: {}, m?: string) {
 }
 
 export function isNumber(s: string): boolean {
-    return Number(s) !== NaN;
+    return !Number.isNaN(Number(s));
 }
 
 /**