diff --git a/src/Gifitti/Gifitti/View_Models/MainForm.cs b/src/Gifitti/Gifitti/View_Models/MainForm.cs
index 7c911822c2c0afcf9b5d69b2f8dafb7eba09a32c..ba8aa8c506b4fd5afa203072d61134dc1cbd9ab4 100644
--- a/src/Gifitti/Gifitti/View_Models/MainForm.cs
+++ b/src/Gifitti/Gifitti/View_Models/MainForm.cs
@@ -178,7 +178,7 @@ namespace Gifitti.View_Models
         {
             int start = 0;
             bool pass = int.TryParse(textBox1.Text, out start);
-            if (pass & start >= 0)
+            if (pass && start >= 0 && start < gm.numberOfFrames)
             {
                 gm.startFrame = start;
             }