diff --git a/src/lib/server/db/schema/user.ts b/src/lib/server/db/schema/user.ts
index 5d70e00..c98fa01 100644
--- a/src/lib/server/db/schema/user.ts
+++ b/src/lib/server/db/schema/user.ts
@@ -4,4 +4,5 @@ export const user = sqliteTable("user", {
   id: integer("id").primaryKey({ autoIncrement: true }),
   email: text("email").notNull().unique(),
   password: text("password").notNull(),
+  nickname: text("nickname").notNull(),
 });
diff --git a/src/lib/server/db/session.ts b/src/lib/server/db/session.ts
index 276090a..b51bf85 100644
--- a/src/lib/server/db/session.ts
+++ b/src/lib/server/db/session.ts
@@ -1,5 +1,5 @@
 import { SqliteError } from "better-sqlite3";
-import { and, eq, gt, lte, isNull } from "drizzle-orm";
+import { and, eq, ne, gt, lte, isNull } from "drizzle-orm";
 import env from "$lib/server/loadenv";
 import db from "./drizzle";
 import { IntegrityError } from "./error";
@@ -71,6 +71,10 @@ export const deleteSession = async (sessionId: string) => {
   await db.delete(session).where(eq(session.id, sessionId));
 };
 
+export const deleteAllOtherSessions = async (userId: number, sessionId: string) => {
+  await db.delete(session).where(and(eq(session.userId, userId), ne(session.id, sessionId)));
+};
+
 export const cleanupExpiredSessions = async () => {
   await db.delete(session).where(lte(session.lastUsedAt, new Date(Date.now() - env.session.exp)));
 };
diff --git a/src/lib/server/db/user.ts b/src/lib/server/db/user.ts
index 1efe43a..d970438 100644
--- a/src/lib/server/db/user.ts
+++ b/src/lib/server/db/user.ts
@@ -2,7 +2,20 @@ import { eq } from "drizzle-orm";
 import db from "./drizzle";
 import { user } from "./schema";
 
+export const getUser = async (userId: number) => {
+  const users = await db.select().from(user).where(eq(user.id, userId)).limit(1);
+  return users[0] ?? null;
+};
+
 export const getUserByEmail = async (email: string) => {
   const users = await db.select().from(user).where(eq(user.email, email)).limit(1);
   return users[0] ?? null;
 };
+
+export const setUserPassword = async (userId: number, password: string) => {
+  await db.update(user).set({ password }).where(eq(user.id, userId));
+};
+
+export const setUserNickname = async (userId: number, nickname: string) => {
+  await db.update(user).set({ nickname }).where(eq(user.id, userId));
+};
diff --git a/src/lib/server/schemas/auth.ts b/src/lib/server/schemas/auth.ts
index 91858c9..2d800d0 100644
--- a/src/lib/server/schemas/auth.ts
+++ b/src/lib/server/schemas/auth.ts
@@ -1,5 +1,11 @@
 import { z } from "zod";
 
+export const changePasswordRequest = z.object({
+  oldPassword: z.string().trim().nonempty(),
+  newPassword: z.string().trim().nonempty(),
+});
+export type ChangePasswordRequest = z.infer<typeof changePasswordRequest>;
+
 export const loginRequest = z.object({
   email: z.string().email().nonempty(),
   password: z.string().trim().nonempty(),
diff --git a/src/lib/server/schemas/index.ts b/src/lib/server/schemas/index.ts
index 615e2bc..6f8270b 100644
--- a/src/lib/server/schemas/index.ts
+++ b/src/lib/server/schemas/index.ts
@@ -4,3 +4,4 @@ export * from "./directory";
 export * from "./file";
 export * from "./hsk";
 export * from "./mek";
+export * from "./user";
diff --git a/src/lib/server/schemas/user.ts b/src/lib/server/schemas/user.ts
new file mode 100644
index 0000000..9841fba
--- /dev/null
+++ b/src/lib/server/schemas/user.ts
@@ -0,0 +1,12 @@
+import { z } from "zod";
+
+export const userInfoResponse = z.object({
+  email: z.string().email().nonempty(),
+  nickname: z.string().nonempty(),
+});
+export type UserInfoResponse = z.infer<typeof userInfoResponse>;
+
+export const changeNicknameRequest = z.object({
+  newNickname: z.string().min(2).max(8),
+});
+export type ChangeNicknameRequest = z.infer<typeof changeNicknameRequest>;
diff --git a/src/lib/server/services/auth.ts b/src/lib/server/services/auth.ts
index c3fee31..81f0333 100644
--- a/src/lib/server/services/auth.ts
+++ b/src/lib/server/services/auth.ts
@@ -5,18 +5,46 @@ import { IntegrityError } from "$lib/server/db/error";
 import {
   upgradeSession,
   deleteSession,
+  deleteAllOtherSessions,
   registerSessionUpgradeChallenge,
   consumeSessionUpgradeChallenge,
 } from "$lib/server/db/session";
-import { getUserByEmail } from "$lib/server/db/user";
+import { getUser, getUserByEmail, setUserPassword } from "$lib/server/db/user";
 import env from "$lib/server/loadenv";
 import { startSession } from "$lib/server/modules/auth";
 import { verifySignature, generateChallenge } from "$lib/server/modules/crypto";
 
+const hashPassword = async (password: string) => {
+  return await argon2.hash(password);
+};
+
 const verifyPassword = async (hash: string, password: string) => {
   return await argon2.verify(hash, password);
 };
 
+export const changePassword = async (
+  userId: number,
+  sessionId: string,
+  oldPassword: string,
+  newPassword: string,
+) => {
+  if (oldPassword === newPassword) {
+    error(400, "Same passwords");
+  } else if (newPassword.length < 8) {
+    error(400, "Too short password");
+  }
+
+  const user = await getUser(userId);
+  if (!user) {
+    error(500, "Invalid session id");
+  } else if (!(await verifyPassword(user.password, oldPassword))) {
+    error(403, "Invalid password");
+  }
+
+  await setUserPassword(userId, await hashPassword(newPassword));
+  await deleteAllOtherSessions(userId, sessionId);
+};
+
 export const login = async (email: string, password: string, ip: string, userAgent: string) => {
   const user = await getUserByEmail(email);
   if (!user || !(await verifyPassword(user.password, password))) {
diff --git a/src/lib/server/services/user.ts b/src/lib/server/services/user.ts
new file mode 100644
index 0000000..5c06458
--- /dev/null
+++ b/src/lib/server/services/user.ts
@@ -0,0 +1,15 @@
+import { error } from "@sveltejs/kit";
+import { getUser, setUserNickname } from "$lib/server/db/user";
+
+export const getUserInformation = async (userId: number) => {
+  const user = await getUser(userId);
+  if (!user) {
+    error(500, "Invalid session id");
+  }
+
+  return { email: user.email, nickname: user.nickname };
+};
+
+export const changeNickname = async (userId: number, nickname: string) => {
+  await setUserNickname(userId, nickname);
+};
diff --git a/src/routes/api/auth/changePassword/+server.ts b/src/routes/api/auth/changePassword/+server.ts
new file mode 100644
index 0000000..a0fbb8d
--- /dev/null
+++ b/src/routes/api/auth/changePassword/+server.ts
@@ -0,0 +1,16 @@
+import { error, text } from "@sveltejs/kit";
+import { authorize } from "$lib/server/modules/auth";
+import { changePasswordRequest } from "$lib/server/schemas";
+import { changePassword } from "$lib/server/services/auth";
+import type { RequestHandler } from "./$types";
+
+export const POST: RequestHandler = async ({ locals, request }) => {
+  const { sessionId, userId } = await authorize(locals, "any");
+
+  const zodRes = changePasswordRequest.safeParse(await request.json());
+  if (!zodRes.success) error(400, "Invalid request body");
+  const { oldPassword, newPassword } = zodRes.data;
+
+  await changePassword(userId, sessionId, oldPassword, newPassword);
+  return text("Password changed", { headers: { "Content-Type": "text/plain" } });
+};
diff --git a/src/routes/api/user/+server.ts b/src/routes/api/user/+server.ts
new file mode 100644
index 0000000..b10b13e
--- /dev/null
+++ b/src/routes/api/user/+server.ts
@@ -0,0 +1,11 @@
+import { json } from "@sveltejs/kit";
+import { authorize } from "$lib/server/modules/auth";
+import { userInfoResponse, type UserInfoResponse } from "$lib/server/schemas";
+import { getUserInformation } from "$lib/server/services/user";
+import type { RequestHandler } from "./$types";
+
+export const GET: RequestHandler = async ({ locals }) => {
+  const { userId } = await authorize(locals, "any");
+  const { email, nickname } = await getUserInformation(userId);
+  return json(userInfoResponse.parse({ email, nickname } satisfies UserInfoResponse));
+};
diff --git a/src/routes/api/user/changeNickname/+server.ts b/src/routes/api/user/changeNickname/+server.ts
new file mode 100644
index 0000000..ab4f887
--- /dev/null
+++ b/src/routes/api/user/changeNickname/+server.ts
@@ -0,0 +1,16 @@
+import { error, text } from "@sveltejs/kit";
+import { authorize } from "$lib/server/modules/auth";
+import { changeNicknameRequest } from "$lib/server/schemas";
+import { changeNickname } from "$lib/server/services/user";
+import type { RequestHandler } from "./$types";
+
+export const POST: RequestHandler = async ({ locals, request }) => {
+  const { userId } = await authorize(locals, "any");
+
+  const zodRes = changeNicknameRequest.safeParse(await request.json());
+  if (!zodRes.success) error(400, "Invalid request body");
+  const { newNickname } = zodRes.data;
+
+  await changeNickname(userId, newNickname);
+  return text("Nickname changed", { headers: { "Content-Type": "text/plain" } });
+};