diff --git a/web/src/components/DateInput.vue b/web/src/components/DateInput.vue
index 2b3d3a2..fbe9d2a 100644
--- a/web/src/components/DateInput.vue
+++ b/web/src/components/DateInput.vue
@@ -3,6 +3,8 @@ const props = defineProps(["modelValue"]);
 const emit = defineEmits(['update:modelValue']);
 
 function dateToYYYYMMDD(d: Date) : string {
+  if(d == null)
+    return "";
   // alternative implementations in https://stackoverflow.com/q/23593052/1850609
   //return new Date(d.getTime() - (d.getTimezoneOffset() * 60 * 1000)).toISOString().split('T')[0];
   return d.toISOString().split('T')[0];