diff --git a/pkgs/applications/science/math/qalculate-gtk/default.nix b/pkgs/applications/science/math/qalculate-gtk/default.nix
index e393111590a..213530b60a9 100644
--- a/pkgs/applications/science/math/qalculate-gtk/default.nix
+++ b/pkgs/applications/science/math/qalculate-gtk/default.nix
@@ -25,6 +25,7 @@ stdenv.mkDerivation rec {
     description = "The ultimate desktop calculator";
     homepage = "http://qalculate.github.io";
     maintainers = with maintainers; [ gebner ];
+    license = licenses.gpl2Plus;
     platforms = platforms.all;
   };
 }