diff --git a/RMuseum/Utils/GanjoorCommentRankingScoreCalculator.cs b/RMuseum/Utils/GanjoorCommentRankingScoreCalculator.cs
new file mode 100644
index 00000000..d8f68a6b
--- /dev/null
+++ b/RMuseum/Utils/GanjoorCommentRankingScoreCalculator.cs
@@ -0,0 +1,48 @@
+using System;
+
+namespace RMuseum.Utils
+{
+    /// <summary>
+    /// comment ranking score calculator
+    /// </summary>
+    public class GanjoorCommentRankingScoreCalculator
+    {
+        public static int ComputeRankingScore(int likes, int dislikes)
+        {
+            int score = likes - dislikes;
+            int votes = likes + dislikes;
+
+            int confidence =
+                VoteConfidenceBonus[
+                    Math.Min(votes, VoteConfidenceBonus.Length - 1)];
+
+            return score * 1_000_000
+                 + confidence * 1_000
+                 + likes;
+        }
+        private static readonly short[] VoteConfidenceBonus =
+        {
+              0, //0 votes
+            200, //1
+            350, //2
+            470, //3
+            560, //4
+            630, //5
+            690, //6
+            740, //7
+            780, //8
+            810, //9
+            840, //10
+            860, //11
+            880, //12
+            895, //13
+            910, //14
+            920, //15
+            930, //16
+            940, //17
+            948, //18
+            955, //19
+            960  //20+
+        };
+    }
+}