diff --git a/tools/inspect-cli.js b/tools/inspect-cli.js
new file mode 100644
index 0000000..a14c081
--- /dev/null
+++ b/tools/inspect-cli.js
@@ -0,0 +1,39 @@
+/**
+ * This tool lets you test if the compiled Javascript decoder is functioning properly. You'll
+ * need to download a SpiderMonkey js-shell to run this script.
+ * https://archive.mozilla.org/pub/firefox/nightly/latest-mozilla-central/
+ *
+ * Example:
+ *   js-shell inspect-cli.js video.ivf
+ */
+load("inspect.js");
+var buffer = read(scriptArgs[0], "binary");
+var Module = {
+  noExitRuntime: true,
+  noInitialRun: true,
+  preInit: [],
+  preRun: [],
+  postRun: [function () {
+    printErr(`Loaded Javascript Decoder OK`);
+  }],
+  memoryInitializerPrefixURL: "bin/",
+  arguments: ['input.ivf', 'output.raw'],
+  on_frame_decoded_json: function (jsonString) {
+    let json = JSON.parse("[" + Module.UTF8ToString(jsonString) + "null]");
+    json.forEach(frame => {
+      if (frame) {
+        print(frame.frame);
+      }
+    });
+  }
+};
+DecoderModule(Module);
+Module.FS.writeFile("/tmp/input.ivf", buffer, { encoding: "binary" });
+Module._open_file();
+Module._set_layers(0xFFFFFFFF); // Set this to zero if you want to benchmark decoding.
+while(true) {
+  printErr("Decoding Frame ...");
+  if (Module._read_frame()) {
+    break;
+  }
+}