diff --git a/.env.example b/.env.example
index 08310fe..ebbb089 100644
--- a/.env.example
+++ b/.env.example
@@ -2,4 +2,5 @@ DATA_DIR=./data
 ROOT_DIR=./data
 APP_PORT=4321
 IMAGE=git.atri.dad/atash/chronus:latest
-JWT_SECRET=some-secret
\ No newline at end of file
+JWT_SECRET=some-secret
+ORIGIN=https://chronus.example.com
\ No newline at end of file
diff --git a/docker-compose.yml b/docker-compose.yml
index 5030c80..e7bd7a7 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -9,6 +9,7 @@ services:
       - PORT=4321
       - DATA_DIR=/app/data
       - JWT_SECRET=${JWT_SECRET}
+      - ORIGIN=${ORIGIN}
     volumes:
       - ${ROOT_DIR}:/app/data
     restart: unless-stopped
diff --git a/src/lib/auth.ts b/src/lib/auth.ts
index d59a320..96bf0ca 100644
--- a/src/lib/auth.ts
+++ b/src/lib/auth.ts
@@ -55,6 +55,22 @@ export async function getUserFromToken(token: string) {
   return user ?? null;
 }
 
+/**
+ * Get the public origin and hostname from the ORIGIN environment variable.
+ * This is required for WebAuthn/passkey rpID to match the browser's origin.
+ */
+export function getOrigin(): { hostname: string; origin: string } {
+  const origin = process.env.ORIGIN;
+  if (!origin) {
+    throw new Error("ORIGIN environment variable is not set");
+  }
+  const url = new URL(origin);
+  return {
+    hostname: url.hostname,
+    origin: url.origin,
+  };
+}
+
 export async function hashPassword(password: string) {
   return await bcrypt.hash(password, 10);
 }
diff --git a/src/pages/api/auth/passkey/login/finish.ts b/src/pages/api/auth/passkey/login/finish.ts
index 17d21df..b6b9fb6 100644
--- a/src/pages/api/auth/passkey/login/finish.ts
+++ b/src/pages/api/auth/passkey/login/finish.ts
@@ -3,7 +3,7 @@ import { verifyAuthenticationResponse } from "@simplewebauthn/server";
 import { db } from "../../../../../db";
 import { users, passkeys, passkeyChallenges } from "../../../../../db/schema";
 import { eq, and, gt } from "drizzle-orm";
-import { setAuthCookie } from "../../../../../lib/auth";
+import { setAuthCookie, getOrigin } from "../../../../../lib/auth";
 
 export const POST: APIRoute = async ({ request, cookies }) => {
   const body = await request.json();
@@ -50,11 +50,12 @@ export const POST: APIRoute = async ({ request, cookies }) => {
 
   let verification;
   try {
+    const { origin, hostname } = getOrigin();
     verification = await verifyAuthenticationResponse({
       response: body,
       expectedChallenge: challenge as string,
-      expectedOrigin: new URL(request.url).origin,
-      expectedRPID: new URL(request.url).hostname,
+      expectedOrigin: origin,
+      expectedRPID: hostname,
       credential: {
         id: passkey.id,
         publicKey: new Uint8Array(Buffer.from(passkey.publicKey, "base64")),
diff --git a/src/pages/api/auth/passkey/login/start.ts b/src/pages/api/auth/passkey/login/start.ts
index 409775f..e26b40e 100644
--- a/src/pages/api/auth/passkey/login/start.ts
+++ b/src/pages/api/auth/passkey/login/start.ts
@@ -3,14 +3,17 @@ import { generateAuthenticationOptions } from "@simplewebauthn/server";
 import { db } from "../../../../../db";
 import { passkeyChallenges } from "../../../../../db/schema";
 import { lte } from "drizzle-orm";
+import { getOrigin } from "../../../../../lib/auth";
 
 export const GET: APIRoute = async ({ request }) => {
   await db
     .delete(passkeyChallenges)
     .where(lte(passkeyChallenges.expiresAt, new Date()));
 
+  const { hostname } = getOrigin();
+
   const options = await generateAuthenticationOptions({
-    rpID: new URL(request.url).hostname,
+    rpID: hostname,
     userVerification: "preferred",
   });
 
diff --git a/src/pages/api/auth/passkey/register/finish.ts b/src/pages/api/auth/passkey/register/finish.ts
index 0c81661..c1c89e4 100644
--- a/src/pages/api/auth/passkey/register/finish.ts
+++ b/src/pages/api/auth/passkey/register/finish.ts
@@ -3,6 +3,7 @@ import { verifyRegistrationResponse } from "@simplewebauthn/server";
 import { db } from "../../../../../db";
 import { passkeys, passkeyChallenges } from "../../../../../db/schema";
 import { eq, and, gt } from "drizzle-orm";
+import { getOrigin } from "../../../../../lib/auth";
 
 export const POST: APIRoute = async ({ request, locals }) => {
   const user = locals.user;
@@ -41,11 +42,12 @@ export const POST: APIRoute = async ({ request, locals }) => {
 
   let verification;
   try {
+    const { origin, hostname } = getOrigin();
     verification = await verifyRegistrationResponse({
       response: body,
       expectedChallenge: challenge,
-      expectedOrigin: new URL(request.url).origin,
-      expectedRPID: new URL(request.url).hostname,
+      expectedOrigin: origin,
+      expectedRPID: hostname,
     });
   } catch (error) {
     console.error("Passkey registration verification failed:", error);
diff --git a/src/pages/api/auth/passkey/register/start.ts b/src/pages/api/auth/passkey/register/start.ts
index 4425080..3766dd4 100644
--- a/src/pages/api/auth/passkey/register/start.ts
+++ b/src/pages/api/auth/passkey/register/start.ts
@@ -3,6 +3,7 @@ import { generateRegistrationOptions } from "@simplewebauthn/server";
 import { db } from "../../../../../db";
 import { passkeys, passkeyChallenges } from "../../../../../db/schema";
 import { eq, lte } from "drizzle-orm";
+import { getOrigin } from "../../../../../lib/auth";
 
 export const GET: APIRoute = async ({ request, locals }) => {
   const user = locals.user;
@@ -21,9 +22,11 @@ export const GET: APIRoute = async ({ request, locals }) => {
     where: eq(passkeys.userId, user.id),
   });
 
+  const { hostname } = getOrigin();
+
   const options = await generateRegistrationOptions({
     rpName: "Chronus",
-    rpID: new URL(request.url).hostname,
+    rpID: hostname,
     userName: user.email,
     attestationType: "none",
     excludeCredentials: userPasskeys.map((passkey) => ({