diff --git a/C#_Version/DeconEngineTests/DeconEngineTests.csproj b/C#_Version/DeconEngineTests/DeconEngineTests.csproj
index 9cc5d09..beb8ad2 100644
--- a/C#_Version/DeconEngineTests/DeconEngineTests.csproj
+++ b/C#_Version/DeconEngineTests/DeconEngineTests.csproj
@@ -112,6 +112,7 @@
     <Compile Include="TestMolecularFormula.cs" />
     <Compile Include="TestThermoFinnigan.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="ValueToStringTests.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\DeconEngine\DeconEngine.csproj">
diff --git a/C#_Version/DeconEngineTests/ValueToStringTests.cs b/C#_Version/DeconEngineTests/ValueToStringTests.cs
new file mode 100644
index 0000000..404fcfd
--- /dev/null
+++ b/C#_Version/DeconEngineTests/ValueToStringTests.cs
@@ -0,0 +1,69 @@
+using System;
+using NUnit.Framework;
+
+namespace DeconEngineTests
+{
+    class ValueToStringTests
+    {
+        [Test]
+        [TestCase(1, 7, "1")]
+        [TestCase(1.2, 7, "1.2")]
+        [TestCase(1.23, 7, "1.23")]
+        [TestCase(1.242, 7, "1.242")]
+        [TestCase(1.2534, 7, "1.2534")]
+        [TestCase(1.25343, 7, "1.25343")]
+        [TestCase(1.25347, 7, "1.25347")]
+        [TestCase(13432, 7, "13432")]
+        [TestCase(132.2, 5, "132.2")]
+        [TestCase(1322.2, 5, "1322.2")]
+        [TestCase(13226.2, 5, "13226")]
+        [TestCase(132296.2, 5, "1.323E+05")]
+        [TestCase(1322969.2, 5, "1.323E+06")]
+        [TestCase(13432.2123, 5, "13432")]
+        [TestCase(113432.2242, 5, "1.1343E+05")]
+        [TestCase(113432.22534, 5, "1.1343E+05")]
+        [TestCase(113432.22534, 9, "1.13432225E+05")]
+        [TestCase(1134323423.673, 7, "1.134323E+09")]
+        [TestCase(11343234235.87, 7, "1.134323E+10")]
+        [TestCase(513432342357.87, 7, "5.134323E+11")]
+        public void TestValueToString1(double value, byte digitsOfPrecision, string expectedResult)
+        {
+            var result = PRISM.StringUtilities.ValueToString(value, digitsOfPrecision, 1e5);
+
+            Console.WriteLine("{0} with {1} digits -> {2}", value, digitsOfPrecision, result);
+
+            Assert.AreEqual(expectedResult, result);
+        }
+
+        [Test]
+        [TestCase(1, 7, "1")]
+        [TestCase(1.2, 7, "1.2")]
+        [TestCase(1.23, 7, "1.23")]
+        [TestCase(1.242, 7, "1.242")]
+        [TestCase(1.2534, 7, "1.2534")]
+        [TestCase(1.25343, 7, "1.25343")]
+        [TestCase(1.25347, 7, "1.25347")]
+        [TestCase(13432, 7, "13432")]
+        [TestCase(132.2, 5, "132.2")]
+        [TestCase(1322.2, 5, "1322.2")]
+        [TestCase(13226.2, 5, "13226")]
+        [TestCase(132296.2, 5, "132296")]
+        [TestCase(1322969.2, 5, "1322969")]
+        [TestCase(13432.2123, 5, "13432")]
+        [TestCase(113432.2242, 5, "113432")]
+        [TestCase(113432.22534, 5, "113432")]
+        [TestCase(113432.22534, 9, "113432.225")]
+        [TestCase(1134323423.673, 7, "1134323424")]
+        [TestCase(11343234235.87, 7, "1.134323E+10")]
+        [TestCase(513432342357.87, 7, "5.134323E+11")]
+        public void TestValueToString2(double value, byte digitsOfPrecision, string expectedResult)
+        {
+            var result = PRISM.StringUtilities.ValueToString(value, digitsOfPrecision, 1e10);
+
+            Console.WriteLine("{0} with {1} digits -> {2}", value, digitsOfPrecision, result);
+
+            Assert.AreEqual(expectedResult, result);
+
+        }
+    }
+}