diff --git a/osu.Game/Rulesets/Mods/ModHardRock.cs b/osu.Game/Rulesets/Mods/ModHardRock.cs
index fe1529d0dc..f33f46a207 100644
--- a/osu.Game/Rulesets/Mods/ModHardRock.cs
+++ b/osu.Game/Rulesets/Mods/ModHardRock.cs
@@ -18,10 +18,10 @@ namespace osu.Game.Rulesets.Mods
         public void ApplyToDifficulty(BeatmapDifficulty difficulty)
         {
             const float ratio = 1.4f;
-            difficulty.CircleSize *= ratio;
+            difficulty.CircleSize *= 1.3f; // CS uses a custom 1.3 ratio.
             difficulty.ApproachRate *= ratio;
             difficulty.DrainRate *= ratio;
             difficulty.OverallDifficulty *= ratio;
         }
     }
-}
\ No newline at end of file
+}