diff --git a/src/main/java/io/takima/Yatzy.java b/src/main/java/io/takima/Yatzy.java
index 5d4d0ec6aac4227dcdd78ba6dbcc116bc2a15b63..a3707012f8f247eba34492898928cf4d0a57ab57 100644
--- a/src/main/java/io/takima/Yatzy.java
+++ b/src/main/java/io/takima/Yatzy.java
@@ -42,6 +42,10 @@ public final class Yatzy {
         return sumDiceThatMatchWithValue(roll, 5);
     }
 
+    public static int sixes(Roll roll) {
+        return sumDiceThatMatchWithValue(roll, 6);
+    }
+
     public static int pair(int d1, int d2, int d3, int d4, int d5) {
         int[] counts = new int[6];
         counts[d1 - 1]++;
@@ -178,14 +182,4 @@ public final class Yatzy {
         else
             return 0;
     }
-
-    public int sixes() {
-        int sum = 0;
-        for (int at = 0; at < dice.length; at++) {
-            if (dice[at] == 6) {
-                sum = sum + 6;
-            }
-        }
-        return sum;
-    }
 }
diff --git a/src/test/java/io/takima/YatzyTest.java b/src/test/java/io/takima/YatzyTest.java
index b37b6884249dff794c9ad14a432754004d33c9dc..f2bb57eb03244b261e6fde8ba8c0be914ef40d6c 100644
--- a/src/test/java/io/takima/YatzyTest.java
+++ b/src/test/java/io/takima/YatzyTest.java
@@ -75,9 +75,9 @@ class YatzyTest {
     @Test
     void sixesShouldSumAllSixDices() {
         assertAll(
-            () -> assertEquals(0, new Yatzy(4, 4, 4, 5, 5).sixes()),
-            () -> assertEquals(6, new Yatzy(4, 4, 6, 5, 5).sixes()),
-            () -> assertEquals(18, new Yatzy(6, 5, 6, 6, 5).sixes())
+            () -> assertEquals(0, Yatzy.sixes(roll(4, 4, 4, 5, 5))),
+            () -> assertEquals(6, Yatzy.sixes(roll(4, 4, 6, 5, 5))),
+            () -> assertEquals(18, Yatzy.sixes(roll(6, 5, 6, 6, 5)))
         );
     }