diff --git a/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml b/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml
index 6ca87d8..f8bcc5c 100644
--- a/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml
+++ b/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml
@@ -86,7 +86,7 @@
             Header="{x:Static resources:Strings.Menu_FastFlags_Presets_FPSLimit_Title}" 
             Description="{x:Static resources:Strings.Menu_FastFlags_Presets_FPSLimit_Description}" 
             HelpLink="https://github.com/pizzaboxer/bloxstrap/wiki/A-guide-to-FastFlags#framerate-limit">
-            <ui:TextBox Margin="5,0,0,0" Padding="10,5,10,5" Width="200" Text="{Binding FramerateLimit, Mode=TwoWay}" PreviewTextInput="ValidateInt32" />
+            <ui:TextBox Margin="5,0,0,0" Padding="10,5,10,5" Width="200" Text="{Binding FramerateLimit, Mode=TwoWay}" PreviewTextInput="ValidateUInt32" />
         </controls:OptionControl>
 
         <controls:OptionControl 
diff --git a/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml.cs b/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml.cs
index 02872fa..4000faa 100644
--- a/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml.cs
+++ b/Bloxstrap/UI/Elements/Settings/Pages/FastFlagsPage.xaml.cs
@@ -31,6 +31,8 @@ namespace Bloxstrap.UI.Elements.Settings.Pages
             DataContext = new FastFlagsViewModel(this);
         }
 
-        private void ValidateInt32(object sender, TextCompositionEventArgs e) => e.Handled = !Int32.TryParse(e.Text, out int _);
+        private void ValidateInt32(object sender, TextCompositionEventArgs e) => e.Handled = e.Text != "-" && !Int32.TryParse(e.Text, out int _);
+        
+        private void ValidateUInt32(object sender, TextCompositionEventArgs e) => e.Handled = !UInt32.TryParse(e.Text, out uint _);
     }
 }