diff --git a/src/ImageProcessor.UnitTests/Extensions/StringExtensionsUnitTests.cs b/src/ImageProcessor.UnitTests/Extensions/StringExtensionsUnitTests.cs
new file mode 100644
index 000000000..d1fefa395
--- /dev/null
+++ b/src/ImageProcessor.UnitTests/Extensions/StringExtensionsUnitTests.cs
@@ -0,0 +1,91 @@
+// --------------------------------------------------------------------------------------------------------------------
+// <copyright file="StringExtensionsUnitTests.cs" company="James South">
+//   Copyright (c) James South.
+//   Licensed under the Apache License, Version 2.0.
+// </copyright>
+// <summary>
+//   Provides a test harness for the string extensions
+// </summary>
+// --------------------------------------------------------------------------------------------------------------------
+
+namespace ImageProcessor.UnitTests
+{
+    using System;
+    using Common.Extensions;
+    using NUnit.Framework;
+
+    /// <summary>
+    /// Test harness for the string extensions
+    /// </summary>
+    [TestFixture]
+    public class StringExtensionsUnitTests
+    {
+        /// <summary>
+        /// Tests the MD5 fingerprint
+        /// </summary>
+        /// <param name="input">The input value</param>
+        /// <param name="expected">The expexted output of the hash</param>
+        [Test]
+        [TestCase("test input", "2e7f7a62eabf0993239ca17c78c464d9")]
+        [TestCase("lorem ipsum dolor", "96ee002fee25e8b675a477c9750fa360")]
+        [TestCase("LoReM IpSuM DoLoR", "41e201da794c7fbdb8ce5526a71c8c83")]
+        [TestCase("1234567890", "e15e31c3d8898c92ab172a4311be9e84")]
+        public void TestToMd5Fingerprint(string input, string expected)
+        {
+            var result = input.ToMD5Fingerprint();
+            var comparison = result.Equals(expected, StringComparison.InvariantCultureIgnoreCase);
+            Assert.True(comparison);
+        }
+
+        /// <summary>
+        /// Tests the SHA-1 fingerprint
+        /// </summary>
+        /// <param name="input">The input value</param>
+        /// <param name="expected">The expexted output of the hash</param>
+        [Test]
+        [TestCase("test input", "49883b34e5a0f48224dd6230f471e9dc1bdbeaf5")]
+        [TestCase("lorem ipsum dolor", "75899ad8827a32493928903aecd6e931bf36f967")]
+        [TestCase("LoReM IpSuM DoLoR", "2f44519afae72fc0837b72c6b53cb11338a1f916")]
+        [TestCase("1234567890", "01b307acba4f54f55aafc33bb06bbbf6ca803e9a")]
+        public void TestToSHA1Fingerprint(string input, string expected)
+        {
+            var result = input.ToSHA1Fingerprint();
+            var comparison = result.Equals(expected, StringComparison.InvariantCultureIgnoreCase);
+            Assert.True(comparison);
+        }
+
+        /// <summary>
+        /// Tests the SHA-256 fingerprint
+        /// </summary>
+        /// <param name="input">The input value</param>
+        /// <param name="expected">The expexted output of the hash</param>
+        [Test]
+        [TestCase("test input", "9dfe6f15d1ab73af898739394fd22fd72a03db01834582f24bb2e1c66c7aaeae")]
+        [TestCase("lorem ipsum dolor", "ed03353266c993ea9afb9900a3ca688ddec1656941b1ca15ee1650a022616dfa")]
+        [TestCase("LoReM IpSuM DoLoR", "55f6cb90ba5cd8eeb6f5f16f083ebcd48ea06c34cc5aed8e33246fc3153d3898")]
+        [TestCase("1234567890", "c775e7b757ede630cd0aa1113bd102661ab38829ca52a6422ab782862f268646")]
+        public void TestToSHA256Fingerprint(string input, string expected)
+        {
+            var result = input.ToSHA256Fingerprint();
+            var comparison = result.Equals(expected, StringComparison.InvariantCultureIgnoreCase);
+            Assert.True(comparison);
+        }
+
+        /// <summary>
+        /// Tests the SHA-512 fingerprint
+        /// </summary>
+        /// <param name="input">The input value</param>
+        /// <param name="expected">The expexted output of the hash</param>
+        [Test]
+        [TestCase("test input", "40aa1b203c9d8ee150b21c3c7cda8261492e5420c5f2b9f7380700e094c303b48e62f319c1da0e32eb40d113c5f1749cc61aeb499167890ab82f2cc9bb706971")]
+        [TestCase("lorem ipsum dolor", "cd813e13d1d3919cdccc31c19d8f8b70bd25e9819f8770a011c8c7a6228536e6c9427b338cd732f2da3c0444dfebef838b745cdaf3fd5dcba8db24fc83a3f6ef")]
+        [TestCase("LoReM IpSuM DoLoR", "3e4704d31f838456c0a5f0892afd392fbc79649a029d017b8104ebd00e2816d94ab4629f731765bf655088b130c51f6f47ca2f8b047749dbd992cf45e89ff431")]
+        [TestCase("1234567890", "12b03226a6d8be9c6e8cd5e55dc6c7920caaa39df14aab92d5e3ea9340d1c8a4d3d0b8e4314f1f6ef131ba4bf1ceb9186ab87c801af0d5c95b1befb8cedae2b9")]
+        public void TestToSHA512Fingerprint(string input, string expected)
+        {
+            var result = input.ToSHA512Fingerprint();
+            var comparison = result.Equals(expected, StringComparison.InvariantCultureIgnoreCase);
+            Assert.True(comparison);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/ImageProcessor.UnitTests/ImageProcessor.UnitTests.csproj b/src/ImageProcessor.UnitTests/ImageProcessor.UnitTests.csproj
index b545a11d9..5b6bc12d1 100644
--- a/src/ImageProcessor.UnitTests/ImageProcessor.UnitTests.csproj
+++ b/src/ImageProcessor.UnitTests/ImageProcessor.UnitTests.csproj
@@ -48,6 +48,7 @@
     </Compile>
     <Compile Include="Extensions\DoubleExtensionsUnitTests.cs" />
     <Compile Include="Extensions\IntegerExtensionsUnitTests.cs" />
+    <Compile Include="Extensions\StringExtensionsUnitTests.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <ItemGroup>