diff --git a/UI/WebServerResources/JavascriptAPIExtensions.js b/UI/WebServerResources/JavascriptAPIExtensions.js
index 509b2ed8c..e29f1b347 100644
--- a/UI/WebServerResources/JavascriptAPIExtensions.js
+++ b/UI/WebServerResources/JavascriptAPIExtensions.js
@@ -82,8 +82,14 @@ Date.prototype.sogoDayName = function() {
 Date.prototype.daysUpTo = function(otherDate) {
   var days = new Array();
 
-  var day1 = this.getTime();
-  var day2 = otherDate.getTime();
+  var day1Date = new Date();
+  day1Date.setTime(this.getTime());
+  day1Date.setHours(0, 0, 0, 0);
+  var day2Date = new Date();
+  day2Date.setTime(otherDate.getTime());
+  day2Date.setHours(23, 59, 59, 999);
+  var day1 = day1Date.getTime();
+  var day2 = day2Date.getTime();
 
   var nbrDays = Math.floor((day2 - day1) / 86400000) + 1;
   for (var i = 0; i < nbrDays; i++) {