diff --git a/modules/programs/kitty.nix b/modules/programs/kitty.nix
index e9594ec12..9854fe69c 100644
--- a/modules/programs/kitty.nix
+++ b/modules/programs/kitty.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.programs.kitty;
 
-  eitherStrBoolInt = with types; either str (either bool int);
+  settingsValueType = with types; oneOf [ str bool int float ];
 
   optionalPackage = opt:
     optional (opt != null && opt.package != null) opt.package;
@@ -102,7 +102,7 @@ in {
     };
 
     settings = mkOption {
-      type = types.attrsOf eitherStrBoolInt;
+      type = types.attrsOf settingsValueType;
       default = { };
       example = literalExpression ''
         {
diff --git a/tests/modules/programs/kitty/example-settings-expected.conf b/tests/modules/programs/kitty/example-settings-expected.conf
index aca1b0c18..41a9cb772 100644
--- a/tests/modules/programs/kitty/example-settings-expected.conf
+++ b/tests/modules/programs/kitty/example-settings-expected.conf
@@ -7,6 +7,7 @@ font_size 8
 # Shell integration is sourced and configured manually
 shell_integration no-rc
 
+background_opacity 0.500000
 enable_audio_bell no
 scrollback_lines 10000
 update_check_interval 0
diff --git a/tests/modules/programs/kitty/example-settings.nix b/tests/modules/programs/kitty/example-settings.nix
index 8d609a5ab..8f2e0b894 100644
--- a/tests/modules/programs/kitty/example-settings.nix
+++ b/tests/modules/programs/kitty/example-settings.nix
@@ -17,6 +17,7 @@ with lib;
         scrollback_lines = 10000;
         enable_audio_bell = false;
         update_check_interval = 0;
+        background_opacity = 0.5;
       };
 
       font.name = "DejaVu Sans";