diff --git a/tests/operations/index.mjs b/tests/operations/index.mjs
index 6d5b266f..f198e440 100644
--- a/tests/operations/index.mjs
+++ b/tests/operations/index.mjs
@@ -162,6 +162,7 @@ import "./tests/SymmetricDifference.mjs";
 import "./tests/TakeNthBytes.mjs";
 import "./tests/Template.mjs";
 import "./tests/TextEncodingBruteForce.mjs";
+import "./tests/TextIntegerConverter.mjs";
 import "./tests/ToFromInsensitiveRegex.mjs";
 import "./tests/TranslateDateTimeFormat.mjs";
 import "./tests/Typex.mjs";
diff --git a/tests/operations/tests/TextIntegerConverter.mjs b/tests/operations/tests/TextIntegerConverter.mjs
new file mode 100644
index 00000000..17466564
--- /dev/null
+++ b/tests/operations/tests/TextIntegerConverter.mjs
@@ -0,0 +1,163 @@
+/**
+ * Text-Integer Conversion tests.
+ *
+ * @author p-leriche [philip.leriche@cantab.net]
+ *
+ * @copyright Crown Copyright 2025
+ * @license Apache-2.0
+ */
+import TestRegister from "../../lib/TestRegister.mjs";
+
+TestRegister.addTests([
+    {
+        name: "Text-Integer Conversion quoted string to decimal",
+        input: "\"ABC\"",
+        expectedOutput: "4276803",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion quoted string to hexadecimal",
+        input: "\"ABC\"",
+        expectedOutput: "0x414243",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Hexadecimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion single quoted string to decimal",
+        input: "'Hello'",
+        expectedOutput: "310939249775",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion decimal to string",
+        input: "4276803",
+        expectedOutput: "ABC",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["String"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion hexadecimal to string",
+        input: "0x48656C6C6F",
+        expectedOutput: "Hello",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["String"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion round-trip string.decimal.string",
+        input: "\"Test\"",
+        expectedOutput: "Test",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+            {
+                op: "Text-Integer Conversion",
+                args: ["String"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion round-trip string.hex.string",
+        input: "\"CyberChef\"",
+        expectedOutput: "CyberChef",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Hexadecimal"],
+            },
+            {
+                op: "Text-Integer Conversion",
+                args: ["String"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion unquoted text to decimal",
+        input: "Hi",
+        expectedOutput: "18537",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion single character",
+        input: "\"A\"",
+        expectedOutput: "65",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion hex to decimal conversion",
+        input: "0xFF",
+        expectedOutput: "255",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion decimal to hex conversion",
+        input: "255",
+        expectedOutput: "0xff",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Hexadecimal"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion large number to string",
+        input: "113091951015816448506195587157728348242683688608116",
+        expectedOutput: "Mary had a little cat",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["String"],
+            },
+        ],
+    },
+    {
+        name: "Text-Integer Conversion whitespace handling (quoted)",
+        input: "\"  test  \"",
+        expectedOutput: "2314978187545944096",
+        recipeConfig: [
+            {
+                op: "Text-Integer Conversion",
+                args: ["Decimal"],
+            },
+        ],
+    },
+]);