diff --git a/src/core/config/Categories.json b/src/core/config/Categories.json
index e0d86f6a..61c70c7b 100644
--- a/src/core/config/Categories.json
+++ b/src/core/config/Categories.json
@@ -72,6 +72,8 @@
             "Avro to JSON",
             "CBOR Encode",
             "CBOR Decode",
+            "YAML to JSON",
+            "JSON to YAML",
             "Caret/M-decode",
             "Rison Encode",
             "Rison Decode",
diff --git a/src/core/operations/JSONtoYAML.mjs b/src/core/operations/JSONtoYAML.mjs
new file mode 100644
index 00000000..0d4cc626
--- /dev/null
+++ b/src/core/operations/JSONtoYAML.mjs
@@ -0,0 +1,46 @@
+/**
+ * @author ccarpo [ccarpo@gmx.net]
+ * @copyright Crown Copyright 2021
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation.mjs";
+import OperationError from "../errors/OperationError.mjs";
+import YAML from "yaml";
+
+/**
+ * JSON to YAML operation
+ */
+class JSONtoYAML extends Operation {
+
+    /**
+     * JSONtoYAML constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "JSON to YAML";
+        this.module = "Default";
+        this.description = "Format a JSON object into YAML";
+        this.infoURL = "https://en.wikipedia.org/wiki/YAML";
+        this.inputType = "JSON";
+        this.outputType = "string";
+        this.args = [];
+    }
+
+    /**
+     * @param {JSON} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        try {
+            return YAML.stringify(input);
+        } catch (err) {
+            throw new OperationError("Test");
+        }
+    }
+
+}
+
+export default JSONtoYAML;
diff --git a/src/core/operations/YAMLToJSON.mjs b/src/core/operations/YAMLToJSON.mjs
new file mode 100644
index 00000000..5b986575
--- /dev/null
+++ b/src/core/operations/YAMLToJSON.mjs
@@ -0,0 +1,45 @@
+/**
+ * @author ccarpo [ccarpo@gmx.net]
+ * @copyright Crown Copyright 2021
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation.mjs";
+import OperationError from "../errors/OperationError.mjs";
+import jsYaml from "js-yaml";
+/**
+ * YAML to JSON operation
+ */
+class YAMLToJSON extends Operation {
+
+    /**
+     * YAMLToJSON constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "YAML to JSON";
+        this.module = "Default";
+        this.description = "Convert YAML to JSON";
+        this.infoURL = "https://en.wikipedia.org/wiki/YAML";
+        this.inputType = "string";
+        this.outputType = "JSON";
+        this.args = [];
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {JSON}
+     */
+    run(input, args) {
+        try {
+            return jsYaml.load(input);
+        } catch (err) {
+            throw new OperationError("Unable to parse YAML: " + err);
+        }
+    }
+
+}
+
+export default YAMLToJSON;
diff --git a/tests/operations/index.mjs b/tests/operations/index.mjs
index 43426275..f78a1890 100644
--- a/tests/operations/index.mjs
+++ b/tests/operations/index.mjs
@@ -161,6 +161,16 @@ import "./tests/TranslateDateTimeFormat.mjs";
 import "./tests/Typex.mjs";
 import "./tests/UnescapeString.mjs";
 import "./tests/Unicode.mjs";
+import "./tests/RSA.mjs";
+import "./tests/CBOREncode.mjs";
+import "./tests/CBORDecode.mjs";
+import "./tests/JA3Fingerprint.mjs";
+import "./tests/JA3SFingerprint.mjs";
+import "./tests/HASSH.mjs";
+import "./tests/JSONtoYAML.mjs";
+
+// Cannot test operations that use the File type yet
+// import "./tests/SplitColourChannels.mjs";
 import "./tests/YARA.mjs";
 import "./tests/ParseCSR.mjs";
 import "./tests/XXTEA.mjs";
diff --git a/tests/operations/tests/JSONtoYAML.mjs b/tests/operations/tests/JSONtoYAML.mjs
new file mode 100644
index 00000000..b18998e9
--- /dev/null
+++ b/tests/operations/tests/JSONtoYAML.mjs
@@ -0,0 +1,41 @@
+/**
+ * YAML tests.
+ *
+ * @author ccarpo [ccarpo@gmx.net]
+ *
+ * @copyright Crown Copyright 2021
+ * @license Apache-2.0
+ */
+import TestRegister from "../../lib/TestRegister.mjs";
+
+const EXAMPLE_YAML = `number: 3\nplain: string\nblock: |\n  two\n  lines`;
+const EXAMPLE_JSON = `{ "number": 3, "plain": "string" }`;
+
+TestRegister.addTests([
+    {
+        name: "YAML to JSON",
+        input: EXAMPLE_YAML,
+        expectedOutput: JSON.stringify({
+            "number": 3,
+            "plain": "string",
+            "block": "two\nlines\n"
+        }, null, 4),
+        recipeConfig: [
+            {
+                op: "YAML to JSON",
+                args: [],
+            }
+        ],
+    },
+    {
+        name: "JSON to YAML",
+        input: EXAMPLE_JSON,
+        expectedOutput: `number: 3\nplain: string\n`,
+        recipeConfig: [
+            {
+                op: "JSON to YAML",
+                args: [],
+            }
+        ],
+    },
+]);