diff --git a/addons/web/static/src/js/formats.js b/addons/web/static/src/js/formats.js
index 0c3577b2671..cf53d9fb3f0 100644
--- a/addons/web/static/src/js/formats.js
+++ b/addons/web/static/src/js/formats.js
@@ -264,6 +264,11 @@ instance.web.parse_value = function (value, descriptor, value_if_empty) {
         case 'datetime':
             var datetime = Date.parseExact(
                     value, (date_pattern + ' ' + time_pattern));
+            if (datetime !== null)
+                return instance.web.datetime_to_str(datetime);
+            datetime = Date.parseExact(value.replace(/\d+/g, function(m){
+                return m.length === 1 ? "0" + m : m ;
+            }), (date_pattern + ' ' + time_pattern));
             if (datetime !== null)
                 return instance.web.datetime_to_str(datetime);
             datetime = Date.parse(value);
@@ -272,6 +277,11 @@ instance.web.parse_value = function (value, descriptor, value_if_empty) {
             throw new Error(_.str.sprintf(_t("'%s' is not a correct datetime"), value));
         case 'date':
             var date = Date.parseExact(value, date_pattern);
+            if (date !== null)
+                return instance.web.date_to_str(date);
+            date = Date.parseExact(value.replace(/\d+/g, function(m){
+                return m.length === 1 ? "0" + m : m ;
+            }), date_pattern);
             if (date !== null)
                 return instance.web.date_to_str(date);
             date = Date.parse(value);