diff --git a/pkg/sudoku/constants.go b/pkg/sudoku/constants.go
index 933720e..f883339 100644
--- a/pkg/sudoku/constants.go
+++ b/pkg/sudoku/constants.go
@@ -1,5 +1,7 @@
 package sudoku
 
+const maxFillFactor = 50
+
 var basicGrid [9][9]int = [9][9]int{
 	{1, 2, 3, 4, 5, 6, 7, 8, 9},
 	{4, 5, 6, 7, 8, 9, 1, 2, 3},
diff --git a/pkg/sudoku/preparation.go b/pkg/sudoku/preparation.go
index 7ce2049..ad0434d 100644
--- a/pkg/sudoku/preparation.go
+++ b/pkg/sudoku/preparation.go
@@ -3,7 +3,7 @@ package sudoku
 import "github.com/cheatsnake/shadify/internal/helpers"
 
 func prepare(grid [9][9]int, fillFactor int) [9][9]int {
-	if fillFactor > 99 {
+	if fillFactor > maxFillFactor {
 		return grid
 	}
 	if fillFactor < 0 {