diff --git a/PKHeX.WinForms/Subforms/Save Editors/SAV_Inventory.cs b/PKHeX.WinForms/Subforms/Save Editors/SAV_Inventory.cs
index 503e99f88..93d853990 100644
--- a/PKHeX.WinForms/Subforms/Save Editors/SAV_Inventory.cs	
+++ b/PKHeX.WinForms/Subforms/Save Editors/SAV_Inventory.cs	
@@ -104,6 +104,7 @@ namespace PKHeX.WinForms
                 dgvIndex.DisplayIndex = c++;
                 dgvIndex.Width = 45;
                 dgvIndex.DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;
+                ((DataGridViewTextBoxColumn) dgvIndex).MaxInputLength = (int)(Math.Log10(Math.Max(1, pouch.MaxCount)) + 1);
             }
 
             dgv.Columns.Add(dgvItemVal);