--- a/cpp/Color.cpp
+++ b/cpp/Color.cpp
@@ -28,7 +28,7 @@
 
 std::string RgbaData::toString() const
 {
-    return std::format("RGBA({}, {}, {}, {})", m_r, m_g, m_r, m_a);
+    return std::format("RGBA({}, {}, {}, {})", m_r, m_g, m_b, m_a);
 }
 
 RgbaData RgbaData::fromRust(rust::Rgba rustData)