diff --git a/tests/operations/index.mjs b/tests/operations/index.mjs
index 09ebf0fc..51676386 100644
--- a/tests/operations/index.mjs
+++ b/tests/operations/index.mjs
@@ -42,6 +42,7 @@ import "./tests/ExtractEmailAddresses.mjs";
 import "./tests/Fork.mjs";
 import "./tests/FromDecimal.mjs";
 import "./tests/Gzip.mjs";
+import "./tests/Gunzip.mjs";
 import "./tests/Hash.mjs";
 import "./tests/HaversineDistance.mjs";
 import "./tests/Hexdump.mjs";
diff --git a/tests/operations/tests/Gunzip.mjs b/tests/operations/tests/Gunzip.mjs
new file mode 100644
index 00000000..f6e05c2f
--- /dev/null
+++ b/tests/operations/tests/Gunzip.mjs
@@ -0,0 +1,58 @@
+/**
+ * Gunzip Tests.
+ *
+ * @author n1073645 [n1073645@gmail.com]
+ *
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import TestRegister from "../../lib/TestRegister.mjs";
+
+TestRegister.addTests([
+    {
+        name: "Gunzip: No comment, no checksum and no filename",
+        input: "1f8b0800f7c8f85d00ff0dc9dd0180200804e0556ea8262848fb3dc588c6a7e76faa8aeedb726036c68d951f76bf9a0af8aae1f97d9c0c084b02509cbf8c2c000000",
+        expectedOutput: "The quick brown fox jumped over the slow dog",
+        recipeConfig: [
+            {
+                op: "From Hex",
+                args: ["None"]
+            },
+            {
+                op: "Gunzip",
+                args: []
+            }
+        ]
+    },
+    {
+        name: "Gunzip: No comment, no checksum and filename",
+        input: "1f8b080843c9f85d00ff66696c656e616d65000dc9dd0180200804e0556ea8262848fb3dc588c6a7e76faa8aeedb726036c68d951f76bf9a0af8aae1f97d9c0c084b02509cbf8c2c000000",
+        expectedOutput: "The quick brown fox jumped over the slow dog",
+        recipeConfig: [
+            {
+                op: "From Hex",
+                args: ["None"]
+            },
+            {
+                op: "Gunzip",
+                args: []
+            }
+        ]
+    },
+    {
+        name: "Gunzip: Has a comment, no checksum and has a filename",
+        input: "1f8b08186fc9f85d00ff66696c656e616d6500636f6d6d656e74000dc9dd0180200804e0556ea8262848fb3dc588c6a7e76faa8aeedb726036c68d951f76bf9a0af8aae1f97d9c0c084b02509cbf8c2c000000",
+        expectedOutput: "The quick brown fox jumped over the slow dog",
+        recipeConfig: [
+            {
+                op: "From Hex",
+                args: ["None"]
+            },
+            {
+                op: "Gunzip",
+                args: []
+            }
+        ]
+    }
+]);
\ No newline at end of file
diff --git a/tests/operations/tests/Gzip.mjs b/tests/operations/tests/Gzip.mjs
index 2b055ae8..c9b2b8ca 100644
--- a/tests/operations/tests/Gzip.mjs
+++ b/tests/operations/tests/Gzip.mjs
@@ -1,5 +1,5 @@
 /**
- * Gzip tests.
+ * Gzip Tests.
  *
  * @author n1073645 [n1073645@gmail.com]
  *