diff --git a/keywords.txt b/keywords.txt
index 75771ef..89144fd 100644
--- a/keywords.txt
+++ b/keywords.txt
@@ -117,6 +117,7 @@ StopAnimation	KEYWORD2
 RestartAnimation	KEYWORD2
 IsAnimationActive	KEYWORD2
 AnimationDuration	KEYWORD2
+ChangeAnimationDuration	KEYWORD2
 UpdateAnimations	KEYWORD2
 IsPaused	KEYWORD2
 Pause	KEYWORD2
diff --git a/src/NeoPixelAnimator.h b/src/NeoPixelAnimator.h
index 21eb2ad..c49d9ec 100644
--- a/src/NeoPixelAnimator.h
+++ b/src/NeoPixelAnimator.h
@@ -109,6 +109,8 @@ public:
         return _animations[indexAnimation]._duration;
     }
 
+    void ChangeAnimationDuration(uint16_t indexAnimation, uint16_t newDuration);
+
     void UpdateAnimations();
 
     bool IsPaused()
@@ -159,6 +161,11 @@ private:
             _remaining = 0;
         }
 
+        float CurrentProgress()
+        {
+            return (float)(_duration - _remaining) / (float)_duration;
+        }
+
         uint16_t _duration;
         uint16_t _remaining;
        
diff --git a/src/internal/NeoPixelAnimator.cpp b/src/internal/NeoPixelAnimator.cpp
index db51a5d..d535316 100644
--- a/src/internal/NeoPixelAnimator.cpp
+++ b/src/internal/NeoPixelAnimator.cpp
@@ -142,7 +142,7 @@ void NeoPixelAnimator::UpdateAnimations()
                 if (pAnim->_remaining > delta)
                 {
                     param.state = (pAnim->_remaining == pAnim->_duration) ? AnimationState_Started : AnimationState_Progress;
-                    param.progress = (float)(pAnim->_duration - pAnim->_remaining) / (float)pAnim->_duration;
+                    param.progress = pAnim->CurrentProgress();
 
                     fnUpdate(param);
 
@@ -164,3 +164,33 @@ void NeoPixelAnimator::UpdateAnimations()
         }
     }
 }
+
+void NeoPixelAnimator::ChangeAnimationDuration(uint16_t indexAnimation, uint16_t newDuration)
+{
+    if (indexAnimation >= _countAnimations)
+    {
+        return;
+    }
+
+    AnimationContext* pAnim = &_animations[indexAnimation];
+
+    // calc the current animation progress 
+    float progress = pAnim->CurrentProgress();
+
+    // keep progress in range just in case
+    if (progress < 0.0f)
+    {
+        progress = 0.0f;
+    }
+    else if (progress > 1.0f)
+    {
+        progress = 1.0f;
+    }
+
+    // change the duration 
+    pAnim->_duration = newDuration;
+          
+    // _remaining time must also be reset after a duration change; 
+    // use the progress to recalculate it
+    pAnim->_remaining = uint16_t(pAnim->_duration * (1.0f - progress));
+}
\ No newline at end of file