diff --git a/lib/src/utils/formatter/as_you_type_formatter.dart b/lib/src/utils/formatter/as_you_type_formatter.dart
index 411ee6a9d1..f747fa4863 100644
--- a/lib/src/utils/formatter/as_you_type_formatter.dart
+++ b/lib/src/utils/formatter/as_you_type_formatter.dart
@@ -54,9 +54,9 @@ class AsYouTypeFormatter extends TextInputFormatter {
               newValue.selection.end == -1 ? 0 : newValue.selection.end;
 
           if (separatorChars.hasMatch(parsedText)) {
-            String valueInInputIndex = parsedText[offset - 1];
-
             if (offset < parsedText.length) {
+              String valueInInputIndex = parsedText[offset - 1];
+
               int offsetDifference = parsedText.length - offset;
 
               if (offsetDifference < 2) {