diff --git a/cypress/integration/rendering/gantt.spec.js b/cypress/integration/rendering/gantt.spec.js
index 87c5f4bd8..438b80267 100644
--- a/cypress/integration/rendering/gantt.spec.js
+++ b/cypress/integration/rendering/gantt.spec.js
@@ -175,7 +175,7 @@ describe('Gantt diagram', () => {
       Another task     :after a1, 20ms
       section Another
       Another another task      :b1, 20, 12ms
-      Another another another task     :after b1, 24ms
+      Another another another task     :after b1, 0.024s
         `,
       {}
     );
diff --git a/src/diagrams/gantt/ganttDb.js b/src/diagrams/gantt/ganttDb.js
index b69d46518..f6a526759 100644
--- a/src/diagrams/gantt/ganttDb.js
+++ b/src/diagrams/gantt/ganttDb.js
@@ -230,31 +230,31 @@ const getStartDate = function (prevTime, dateFormat, str) {
   return new Date();
 };
 
-const durationToDate = function (durationStatement, relativeTime) {
-  if (durationStatement !== null) {
-    switch (durationStatement[2]) {
-      case 'ms':
-        relativeTime.add(durationStatement[1], 'milliseconds');
-        break;
-      case 's':
-        relativeTime.add(durationStatement[1], 'seconds');
-        break;
-      case 'm':
-        relativeTime.add(durationStatement[1], 'minutes');
-        break;
-      case 'h':
-        relativeTime.add(durationStatement[1], 'hours');
-        break;
-      case 'd':
-        relativeTime.add(durationStatement[1], 'days');
-        break;
-      case 'w':
-        relativeTime.add(durationStatement[1], 'weeks');
-        break;
-    }
+/**
+ * Parse a string as a moment duration.
+ *
+ * The string have to be compound by a value and a shorthand duration unit. For example `5d`
+ * representes 5 days.
+ *
+ * Shorthand unit supported are:
+ *
+ * - `y` for years
+ * - `M` for months
+ * - `w` for weeks
+ * - `d` for days
+ * - `h` for hours
+ * - `s` for seconds
+ * - `ms` for milliseconds
+ *
+ * @param {string} str - A string representing the duration.
+ * @returns {moment.Duration} A moment duration, including an invalid moment for invalid input string.
+ */
+const parseDuration = function (str) {
+  const statement = /^(\d+(?:\.\d+)?)([yMwdhms]|ms)$/.exec(str.trim());
+  if (statement !== null) {
+    return moment.duration(Number.parseFloat(statement[1]), statement[2]);
   }
-  // Default date - now
-  return relativeTime.toDate();
+  return moment.duration.invalid();
 };
 
 const getEndDate = function (prevTime, dateFormat, str, inclusive) {
@@ -270,7 +270,12 @@ const getEndDate = function (prevTime, dateFormat, str, inclusive) {
     return mDate.toDate();
   }
 
-  return durationToDate(/^([\d]+)([wdhms]|ms)$/.exec(str.trim()), moment(prevTime));
+  const endTime = moment(prevTime);
+  const duration = parseDuration(str);
+  if (duration.isValid()) {
+    endTime.add(duration);
+  }
+  return endTime.toDate();
 };
 
 let taskCnt = 0;
@@ -666,7 +671,7 @@ export default {
   setLink,
   getLinks,
   bindFunctions,
-  durationToDate,
+  parseDuration,
   isInvalidDate,
 };
 
diff --git a/src/diagrams/gantt/ganttDb.spec.js b/src/diagrams/gantt/ganttDb.spec.js
index d07aee4bf..4d1c3860b 100644
--- a/src/diagrams/gantt/ganttDb.spec.js
+++ b/src/diagrams/gantt/ganttDb.spec.js
@@ -6,13 +6,16 @@ describe('when using the ganttDb', function () {
     ganttDb.clear();
   });
 
-  describe('when using relative times', function () {
+  describe('when using duration', function () {
     it.each`
-      diff     | date                    | expected
-      ${' 1d'} | ${moment('2019-01-01')} | ${moment('2019-01-02').toDate()}
-      ${' 1w'} | ${moment('2019-01-01')} | ${moment('2019-01-08').toDate()}
-    `('should add $diff to $date resulting in $expected', ({ diff, date, expected }) => {
-      expect(ganttDb.durationToDate(diff, date)).toEqual(expected);
+      str       | expected
+      ${'1d'}   | ${moment.duration(1, 'd')}
+      ${'2w'}   | ${moment.duration(2, 'w')}
+      ${'1ms'}  | ${moment.duration(1, 'ms')}
+      ${'0.1s'} | ${moment.duration(100, 'ms')}
+      ${'1f'}   | ${moment.duration.invalid()}
+    `('should $str resulting in $expected duration', ({ str, expected }) => {
+      expect(ganttDb.parseDuration(str)).toEqual(expected);
     });
   });
 
@@ -106,7 +109,7 @@ describe('when using the ganttDb', function () {
     ganttDb.addTask('test2', 'id2,after id1,5ms');
     ganttDb.addSection('testa2');
     ganttDb.addTask('test3', 'id3,20,10ms');
-    ganttDb.addTask('test4', 'id4,after id3,5ms');
+    ganttDb.addTask('test4', 'id4,after id3,0.005s');
 
     const tasks = ganttDb.getTasks();