diff --git a/server/src/app.ts b/server/src/app.ts
index f948af4..80f3912 100644
--- a/server/src/app.ts
+++ b/server/src/app.ts
@@ -20,14 +20,25 @@ import { collectSystemStatus } from "./status.js";
 import { readUpdateStatus, triggerSystemUpdate } from "./update.js";
 import "./types.js";
 
-const credentialsSchema = z.object({
-  username: z
+const usernameSchema = z
+  .string()
+  .trim()
+  .min(3, "Username must contain at least 3 characters")
+  .max(48, "Username must contain at most 48 characters")
+  .regex(/^[a-zA-Z0-9][a-zA-Z0-9_.-]*$/, "Use letters, numbers, dots, hyphens, or underscores");
+
+const loginCredentialsSchema = z.object({
+  username: usernameSchema,
+  password: z.string().min(1).max(256)
+});
+
+const setupCredentialsSchema = loginCredentialsSchema.extend({
+  password: z
     .string()
-    .trim()
-    .min(3, "Username must contain at least 3 characters")
-    .max(48, "Username must contain at most 48 characters")
-    .regex(/^[a-zA-Z0-9][a-zA-Z0-9_.-]*$/, "Use letters, numbers, dots, hyphens, or underscores"),
-  password: z.string().min(12, "Password must contain at least 12 characters").max(256)
+    .min(8, "Password must contain at least 8 characters")
+    .max(256)
+    .regex(/[A-Z]/, "Password must contain at least one uppercase letter")
+    .regex(/[0-9]/, "Password must contain at least one number")
 });
 
 type UserRow = { id: number; username: string; role: "admin"; password_hash: string };
@@ -162,7 +173,7 @@ export async function buildApp(config: AppConfig): Promise<FastifyInstance> {
     "/api/auth/setup",
     { config: { rateLimit: { max: 5, timeWindow: "1 minute" } } },
     async (request, reply) => {
-      const parsed = credentialsSchema.safeParse(request.body);
+      const parsed = setupCredentialsSchema.safeParse(request.body);
       if (!parsed.success) {
         return reply.code(400).send({
           error: { code: "INVALID_CREDENTIALS", message: parsed.error.issues[0]?.message ?? "Invalid account details" }
@@ -203,7 +214,7 @@ export async function buildApp(config: AppConfig): Promise<FastifyInstance> {
     "/api/auth/login",
     { config: { rateLimit: { max: 8, timeWindow: "1 minute" } } },
     async (request, reply) => {
-      const parsed = credentialsSchema.safeParse(request.body);
+      const parsed = loginCredentialsSchema.safeParse(request.body);
       const user = parsed.success
         ? (database
             .prepare("SELECT id, username, role, password_hash FROM users WHERE username = ? COLLATE NOCASE")
diff --git a/server/tests/app.test.ts b/server/tests/app.test.ts
index f26b53e..d000e63 100644
--- a/server/tests/app.test.ts
+++ b/server/tests/app.test.ts
@@ -45,7 +45,7 @@ async function setup(app: FastifyInstance, token: string) {
     method: "POST",
     url: "/api/auth/setup",
     headers: mutationHeaders(token),
-    payload: { username: "owner", password: "correct-horse-battery-staple" }
+    payload: { username: "owner", password: "Correct-horse1" }
   });
 }
 
@@ -63,19 +63,40 @@ describe("authentication boundary", () => {
       method: "POST",
       url: "/api/auth/setup",
       headers: mutationHeaders(token),
-      payload: { username: "second", password: "another-secure-password" }
+      payload: { username: "second", password: "Another-pass2" }
     });
 
     expect(second.statusCode).toBe(409);
     expect(second.json()).toMatchObject({ error: { code: "SETUP_COMPLETE" } });
   });
 
+  it("requires 8 characters, an uppercase letter, and a number for setup", async () => {
+    const app = await createApp();
+    const token = await csrf(app);
+    const cases = [
+      { password: "Short1", expectedMessage: "at least 8 characters" },
+      { password: "lowercase1", expectedMessage: "uppercase letter" },
+      { password: "NoNumberHere", expectedMessage: "one number" }
+    ];
+
+    for (const testCase of cases) {
+      const response = await app.inject({
+        method: "POST",
+        url: "/api/auth/setup",
+        headers: mutationHeaders(token),
+        payload: { username: "owner", password: testCase.password }
+      });
+      expect(response.statusCode).toBe(400);
+      expect(response.json<{ error: { message: string } }>().error.message).toContain(testCase.expectedMessage);
+    }
+  });
+
   it("rejects state changes without a matching CSRF token", async () => {
     const app = await createApp();
     const response = await app.inject({
       method: "POST",
       url: "/api/auth/setup",
-      payload: { username: "owner", password: "correct-horse-battery-staple" }
+      payload: { username: "owner", password: "Correct-horse1" }
     });
 
     expect(response.statusCode).toBe(403);
@@ -89,7 +110,7 @@ describe("authentication boundary", () => {
       method: "POST",
       url: "/api/auth/setup",
       headers: { ...mutationHeaders(token), origin: "https://attacker.example" },
-      payload: { username: "owner", password: "correct-horse-battery-staple" }
+      payload: { username: "owner", password: "Correct-horse1" }
     });
 
     expect(response.statusCode).toBe(403);
@@ -107,7 +128,7 @@ describe("authentication boundary", () => {
         host: "192.168.4.20:8787",
         origin: "http://192.168.4.20:8787"
       },
-      payload: { username: "owner", password: "correct-horse-battery-staple" }
+      payload: { username: "owner", password: "Correct-horse1" }
     });
 
     expect(response.statusCode).toBe(201);
@@ -123,7 +144,7 @@ describe("authentication boundary", () => {
       method: "POST",
       url: "/api/auth/login",
       headers: mutationHeaders(token),
-      payload: { username: "owner", password: "correct-horse-battery-staple" }
+      payload: { username: "owner", password: "Correct-horse1" }
     });
     expect(login.statusCode).toBe(200);
     const sessionCookie = login.cookies.find((cookie) => cookie.name === SESSION_COOKIE);
diff --git a/web/src/App.tsx b/web/src/App.tsx
index dab5a44..9a1d38e 100644
--- a/web/src/App.tsx
+++ b/web/src/App.tsx
@@ -126,8 +126,18 @@ function AccountScreen({
           </label>
           <label>
             <span>Password</span>
-            <input type="password" autoComplete={setup ? "new-password" : "current-password"} value={password} onChange={(event) => setPassword(event.target.value)} minLength={12} maxLength={256} required />
-            {setup && <small>Use at least 12 characters.</small>}
+            <input
+              type="password"
+              autoComplete={setup ? "new-password" : "current-password"}
+              value={password}
+              onChange={(event) => setPassword(event.target.value)}
+              minLength={setup ? 8 : 1}
+              maxLength={256}
+              pattern={setup ? "(?=.*[A-Z])(?=.*[0-9]).{8,}" : undefined}
+              title={setup ? "Use at least 8 characters, one uppercase letter, and one number." : undefined}
+              required
+            />
+            {setup && <small>Use at least 8 characters, one uppercase letter, and one number.</small>}
           </label>
           {error && <div className="form-error" role="alert"><WarningCircle size={20} />{error}</div>}
           <button className="primary-button" type="submit" disabled={submitting}>