diff --git a/Tests/LibGfx/CMakeLists.txt b/Tests/LibGfx/CMakeLists.txt
index f9582f16f0f..b0705db1665 100644
--- a/Tests/LibGfx/CMakeLists.txt
+++ b/Tests/LibGfx/CMakeLists.txt
@@ -1,6 +1,7 @@
 set(TEST_SOURCES
     BenchmarkGfxPainter.cpp
     BenchmarkJPEGLoader.cpp
+    TestColor.cpp
     TestDeltaE.cpp
     TestFontHandling.cpp
     TestGfxBitmap.cpp
diff --git a/Tests/LibGfx/TestColor.cpp b/Tests/LibGfx/TestColor.cpp
new file mode 100644
index 00000000000..e300d5beaa7
--- /dev/null
+++ b/Tests/LibGfx/TestColor.cpp
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024, Lucas Chollet <lucas.chollet@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibGfx/Color.h>
+#include <LibTest/TestCase.h>
+
+TEST_CASE(color)
+{
+    for (u16 i = 0; i < 256; ++i) {
+        auto const gray = Color(i, i, i);
+        EXPECT_EQ(gray, gray.to_grayscale());
+    }
+}
diff --git a/Userland/Libraries/LibGfx/Color.h b/Userland/Libraries/LibGfx/Color.h
index 60e1a136fc6..853387b6f25 100644
--- a/Userland/Libraries/LibGfx/Color.h
+++ b/Userland/Libraries/LibGfx/Color.h
@@ -316,7 +316,7 @@ public:
 
     constexpr u8 luminosity() const
     {
-        return (red() * 0.2126f + green() * 0.7152f + blue() * 0.0722f);
+        return round_to<u8>(red() * 0.2126f + green() * 0.7152f + blue() * 0.0722f);
     }
 
     constexpr float contrast_ratio(Color other)