diff --git a/src/modules/15_development/components/ProjectDetail.vue b/src/modules/15_development/components/ProjectDetail.vue
index bde2519d2..04a93ee1f 100644
--- a/src/modules/15_development/components/ProjectDetail.vue
+++ b/src/modules/15_development/components/ProjectDetail.vue
@@ -328,7 +328,7 @@ const filterSelector = (val: string, update: Function) => {
 
 function updatetotalDate() {
   if (formData.dateStart && formData.dateEnd) {
-    formData.totalDate = diffDay(formData.dateStart, formData.dateEnd);
+    formData.totalDate = diffDay(formData.dateStart, formData.dateEnd)+1;
   }
 }