diff --git a/scripts/update-constant.ts b/scripts/update-constant.ts
new file mode 100644
index 0000000..f321f56
--- /dev/null
+++ b/scripts/update-constant.ts
@@ -0,0 +1,96 @@
+/**
+ * This script tries to update constant automatically
+ */
+import { path } from "../deps.ts";
+
+const ROOT_DIR = path.resolve(
+  path.dirname(path.fromFileUrl(import.meta.url)),
+  "..",
+);
+const CONSTANT_PATH = path.join(ROOT_DIR, "constant.ts");
+const STORE_URL =
+  "https://apps.apple.com/us/app/nintendo-switch-online/id1234806557";
+const SPLATNET3_URL = "https://api.lp1.av5ja.srv.nintendo.net";
+
+function replaceConst(content: string, name: string, value: string): string {
+  const regex = new RegExp(`export const ${name} = ".*?";\n`);
+
+  return content.replace(regex, `export const ${name} = "${value}";\n`);
+}
+
+function getConst(content: string, name: string): string {
+  const regex = new RegExp(`export const ${name} = (".*?");\n`);
+
+  const match = regex.exec(content);
+
+  if (!match) {
+    throw new Error(`Cannot find ${name}`);
+  }
+
+  return JSON.parse(match[1]);
+}
+
+async function printError<T>(p: Promise<T>): Promise<T | undefined> {
+  try {
+    return await p;
+  } catch (e) {
+    console.error(e);
+    return undefined;
+  }
+}
+
+async function getWebViewVer(): Promise<string> {
+  const splatnet3Home = await (await fetch(SPLATNET3_URL)).text();
+
+  const mainJS = /src="(\/.*?\.js)"/.exec(splatnet3Home)?.[1];
+
+  if (!mainJS) {
+    throw new Error("No main.js found");
+  }
+
+  const mainJSBody = await (await fetch(SPLATNET3_URL + mainJS)).text();
+
+  const revision = /"([0-9a-f]{40})"/.exec(mainJSBody)?.[1];
+  const version = /revision_info_not_set.*?="(\d+\.\d+\.\d+)/.exec(mainJSBody)
+    ?.[1];
+
+  if (!version || !revision) {
+    throw new Error("No version and revision found");
+  }
+
+  const ver = `${version}-${revision.substring(0, 8)}`;
+
+  return ver;
+}
+
+async function getNSOVer(): Promise<string> {
+  const main = await (await fetch(STORE_URL)).text();
+  const ver = />Version (.*?)</.exec(main)?.[1];
+
+  if (!ver) {
+    throw new Error("No version found");
+  }
+
+  return ver;
+}
+
+let content = await Deno.readTextFile(CONSTANT_PATH);
+const oldValues = {
+  WEB_VIEW_VERSION: getConst(content, "WEB_VIEW_VERSION"),
+  NSOAPP_VERSION: getConst(content, "NSOAPP_VERSION"),
+};
+const newValues: Record<string, string | undefined> = {};
+
+newValues.WEB_VIEW_VERSION = await printError(getWebViewVer());
+newValues.NSOAPP_VERSION = await printError(getNSOVer());
+
+for (const [key, value] of Object.entries(newValues)) {
+  if (value) {
+    content = replaceConst(content, key, value);
+  }
+}
+await Deno.writeTextFile(CONSTANT_PATH, content);
+
+console.log("Done");
+console.log("Old:", oldValues);
+console.log("New:", newValues);