diff --git a/src/plugins/timezones/api.ts b/src/plugins/timezones/api.ts
index c9feafe3e..246ffb50d 100644
--- a/src/plugins/timezones/api.ts
+++ b/src/plugins/timezones/api.ts
@@ -9,11 +9,26 @@ import { Logger } from "@utils/Logger";
 
 import settings from "./settings";
 
+export const DEFAULT_API = "https://timezonedb.catvibers.me/api";
+
 export type Snowflake = string;
 type ApiError = { error: string; };
 type UserFetchResponse = ApiError | { timezoneId: string }
 type BulkFetchResponse = ApiError | Record<Snowflake, { timezoneId: string | null }>;
 
+export async function verifyApi(url: string): Promise<boolean> {
+    if (url === DEFAULT_API) return true;
+
+    const res = await fetch(url, {
+        method: "GET",
+        headers: {
+            "User-Agent": VENCORD_USER_AGENT,
+        },
+    });
+
+    return "logged_in" in await res.json();
+}
+
 export async function fetchTimezonesBulk(ids: Snowflake[]): Promise<Record<Snowflake, string | null> | undefined> {
     try {
         const { apiUrl } = settings.store;
@@ -21,7 +36,7 @@ export async function fetchTimezonesBulk(ids: Snowflake[]): Promise<Record<Snowf
             method: "POST",
             headers: {
                 "Content-Type": "application/json",
-                "X-User-Agent": VENCORD_USER_AGENT,
+                "User-Agent": VENCORD_USER_AGENT,
             },
             body: JSON.stringify(ids),
         });
@@ -47,8 +62,7 @@ export async function fetchTimezone(userId: Snowflake): Promise<string | null |
         const req = await fetch(`${apiUrl}/user/${userId}`, {
             method: "GET",
             headers: {
-                "Content-Type": "application/json",
-                "X-User-Agent": VENCORD_USER_AGENT,
+                "User-Agent": VENCORD_USER_AGENT,
             },
         });
 
diff --git a/src/plugins/timezones/index.tsx b/src/plugins/timezones/index.tsx
index b7bca3bf9..43e641b4e 100644
--- a/src/plugins/timezones/index.tsx
+++ b/src/plugins/timezones/index.tsx
@@ -7,10 +7,13 @@
 import { NavContextMenuPatchCallback } from "@api/ContextMenu";
 import { CogWheel } from "@components/Icons";
 import { Devs } from "@utils/constants";
+import { Logger } from "@utils/Logger";
 import definePlugin from "@utils/types";
 import { Menu, UserStore } from "@webpack/common";
 import { Message, User } from "discord-types/general";
+import { Promisable } from "type-fest";
 
+import { verifyApi } from "./api";
 import { LocalTimestamp, openTimezoneOverrideModal } from "./components";
 import settings, { SettingsComponent } from "./settings";
 
@@ -67,6 +70,20 @@ export default definePlugin({
         "user-profile-overflow-menu": contextMenuPatch,
     },
 
+    beforeSave(options: Record<string, any>): Promisable<true | string> {
+        // Check that API url is valid
+        const { apiUrl } = options;
+        if (!apiUrl) return "Invalid API url!";
+
+        return verifyApi(apiUrl).then(success => {
+            if (success) return true;
+            return "Failed to verify API!";
+        }).catch(err => {
+            new Logger("Timezones").info("Failed to verify API url", err);
+            return "Failed to verify API!";
+        });
+    },
+
     renderProfileTimezone: (props?: { user?: User; }) => {
         if (!settings.store.displayInProfile || !props?.user?.id) return null;
 
diff --git a/src/plugins/timezones/settings.tsx b/src/plugins/timezones/settings.tsx
index 282ce8dfd..8c9537c8e 100644
--- a/src/plugins/timezones/settings.tsx
+++ b/src/plugins/timezones/settings.tsx
@@ -19,31 +19,28 @@
 import { DataStore } from "@api/index";
 import { definePluginSettings } from "@api/Settings";
 import { Link } from "@components/Link";
+import { Margins } from "@utils/margins";
+import { classes } from "@utils/misc";
 import { IPluginOptionComponentProps, OptionType } from "@utils/types";
 import { Text } from "@webpack/common";
 
-import { Snowflake } from "./api";
+import { DEFAULT_API, Snowflake } from "./api";
 import { TimezoneCache } from "./cache";
-import { classes } from "@utils/misc";
-import { Margins } from "@utils/margins";
 
 export type TimezoneOverrides = Record<Snowflake, string | null>;
 
-const DEFAULT_API = "https://timezonedb.catvibers.me/api";
-
 const settings = definePluginSettings({
     enableApi: {
         type: OptionType.BOOLEAN,
         description: "Fetch user timezones from TimezoneDB when a local override does not exist",
         default: true,
     },
-    // TODO: disable this if enableApi is disabled
     apiUrl: {
         type: OptionType.STRING,
         description: "The TimezoneDB API instance",
         default: DEFAULT_API,
         placeholder: DEFAULT_API,
-        onChange(_: any) {
+        onChange(_: string) {
             DataStore.clear(TimezoneCache).catch(_ => _);
         },
     },