diff --git a/OpenNest.IO/Bom/Fraction.cs b/OpenNest.Core/Math/Fraction.cs
similarity index 98%
rename from OpenNest.IO/Bom/Fraction.cs
rename to OpenNest.Core/Math/Fraction.cs
index 704fb0a..a369a15 100644
--- a/OpenNest.IO/Bom/Fraction.cs
+++ b/OpenNest.Core/Math/Fraction.cs
@@ -3,7 +3,7 @@ using System.Linq;
 using System.Text;
 using System.Text.RegularExpressions;
 
-namespace OpenNest.IO.Bom
+namespace OpenNest.Math
 {
     public static class Fraction
     {
diff --git a/OpenNest.Tests/Math/FractionTests.cs b/OpenNest.Tests/Math/FractionTests.cs
new file mode 100644
index 0000000..3253e71
--- /dev/null
+++ b/OpenNest.Tests/Math/FractionTests.cs
@@ -0,0 +1,46 @@
+using OpenNest.Math;
+using Xunit;
+
+namespace OpenNest.Tests.Math;
+
+public class FractionTests
+{
+    [Theory]
+    [InlineData("3/8", 0.375)]
+    [InlineData("1 3/4", 1.75)]
+    [InlineData("1-3/4", 1.75)]
+    [InlineData("1/2", 0.5)]
+    public void Parse_ValidFraction_ReturnsDouble(string input, double expected)
+    {
+        var result = Fraction.Parse(input);
+
+        Assert.Equal(expected, result, 8);
+    }
+
+    [Theory]
+    [InlineData("3/8", true)]
+    [InlineData("abc", false)]
+    [InlineData("1 3/4", true)]
+    public void IsValid_ReturnsExpected(string input, bool expected)
+    {
+        Assert.Equal(expected, Fraction.IsValid(input));
+    }
+
+    [Fact]
+    public void TryParse_InvalidInput_ReturnsFalse()
+    {
+        var result = Fraction.TryParse("abc", out var value);
+
+        Assert.False(result);
+        Assert.Equal(0, value);
+    }
+
+    [Fact]
+    public void ReplaceFractionsWithDecimals_ReplacesFractionInString()
+    {
+        var result = Fraction.ReplaceFractionsWithDecimals("length is 1 3/4 inches");
+
+        Assert.Contains("1.75", result);
+        Assert.DoesNotContain("3/4", result);
+    }
+}
diff --git a/OpenNest/ArchUnits.cs b/OpenNest/ArchUnits.cs
index a618bc3..30304ad 100644
--- a/OpenNest/ArchUnits.cs
+++ b/OpenNest/ArchUnits.cs
@@ -1,4 +1,4 @@
-using OpenNest.IO.Bom;
+using OpenNest.Math;
 using System;
 using System.Drawing;
 using System.Text;