diff --git a/src/main/java/org/apache/commons/lang3/time/DurationFormatUtils.java b/src/main/java/org/apache/commons/lang3/time/DurationFormatUtils.java
index 18dc6a49d..01271bff1 100644
--- a/src/main/java/org/apache/commons/lang3/time/DurationFormatUtils.java
+++ b/src/main/java/org/apache/commons/lang3/time/DurationFormatUtils.java
@@ -534,7 +534,7 @@ public static String formatPeriod(final long startMillis, final long endMillis,
         end.setTime(new Date(endMillis));
 
         // initial estimates
-        int milliseconds = end.get(Calendar.MILLISECOND) - start.get(Calendar.MILLISECOND);
+        long milliseconds = end.get(Calendar.MILLISECOND) - start.get(Calendar.MILLISECOND);
         int seconds = end.get(Calendar.SECOND) - start.get(Calendar.SECOND);
         int minutes = end.get(Calendar.MINUTE) - start.get(Calendar.MINUTE);
         int hours = end.get(Calendar.HOUR_OF_DAY) - start.get(Calendar.HOUR_OF_DAY);