diff --git a/core/Api/UserAPI.class.php b/core/Api/UserAPI.class.php
index dc4b86f..d9ec54b 100644
--- a/core/Api/UserAPI.class.php
+++ b/core/Api/UserAPI.class.php
@@ -6,11 +6,25 @@ namespace Api {
 
   abstract class UserAPI extends Request {
 
-    protected function userExists($username, $email) {
+    protected function userExists(?string $username, ?string $email) {
+
+      $conditions = array();
+      if (!is_null($username) && !empty($username)) {
+        $conditions[] = new Compare("User.name", $username);
+      }
+
+      if (!is_null($email) && !empty($email)) {
+        $conditions[] = new Compare("User.email", $email);
+      }
+
+      if (empty($conditions)) {
+        return true;
+      }
+
       $sql = $this->user->getSQL();
       $res = $sql->select("User.name", "User.email")
         ->from("User")
-        ->where(new Compare("User.name", $username), new Compare("User.email", $email))
+        ->where(...$conditions)
         ->execute();
 
       $this->success = ($res !== FALSE);
@@ -70,6 +84,22 @@ namespace Api {
 
       return array();
     }
+
+    protected function getUser($id) {
+      $sql = $this->user->getSQL();
+      $res = $sql->select("User.uid as userId", "User.name", "User.email", "User.registered_at",
+        "Group.uid as groupId", "Group.name as groupName", "Group.color as groupColor")
+        ->from("User")
+        ->leftJoin("UserGroup", "User.uid", "UserGroup.user_id")
+        ->leftJoin("Group", "Group.uid", "UserGroup.group_id")
+        ->where(new Compare("User.uid", $id))
+        ->execute();
+
+      $this->success = ($res !== FALSE);
+      $this->lastError = $sql->getLastError();
+
+      return ($this->success && !empty($res) ? $res : array());
+    }
   }
 
 }
@@ -82,6 +112,7 @@ namespace Api\User {
   use Api\UserAPI;
   use DateTime;
   use Driver\SQL\Condition\Compare;
+  use Objects\User;
 
   class Create extends UserAPI {
 
@@ -104,7 +135,7 @@ namespace Api\User {
 
       $username = $this->getParam('username');
       $email = $this->getParam('email');
-      if (!$this->userExists($username, $email) || !$this->success) {
+      if (!$this->userExists($username, $email)) {
         return false;
       }
 
@@ -232,33 +263,21 @@ namespace Api\User {
       }
 
       $id = $this->getParam("id");
-
-      $sql = $this->user->getSQL();
-      $res = $sql->select("User.uid as userId", "User.name", "User.email", "User.registered_at",
-        "Group.uid as groupId", "Group.name as groupName", "Group.color as groupColor")
-        ->from("User")
-        ->leftJoin("UserGroup", "User.uid", "UserGroup.user_id")
-        ->leftJoin("Group", "Group.uid", "UserGroup.group_id")
-        ->where(new Compare("User.uid", $id))
-        ->execute();
-
-      $this->success = ($res !== FALSE);
-      $this->lastError = $sql->getLastError();
+      $user = $this->getUser($id);
 
       if ($this->success) {
-        if (empty($res)) {
+        if (empty($user)) {
           return $this->createError("User not found");
         } else {
-          $row = $res[0];
           $this->result["user"] = array(
-            "uid" => $row["userId"],
-            "name" => $row["name"],
-            "email" => $row["email"],
-            "registered_at" => $row["registered_at"],
+            "uid" => $user[0]["userId"],
+            "name" => $user[0]["name"],
+            "email" => $user[0]["email"],
+            "registered_at" => $user[0]["registered_at"],
             "groups" => array()
           );
 
-          foreach($res as $row) {
+          foreach($user as $row) {
             $this->result["user"]["groups"][] = array(
               "uid" => $row["groupId"],
               "name" => $row["groupName"],
@@ -548,5 +567,81 @@ If the registration was not intended, you can simply ignore this email.<br><br><
     }
   }
 
+  class Edit extends UserAPI {
 
+    public function __construct(User $user, bool $externalCall) {
+      parent::__construct($user, $externalCall, array(
+        'id' => new Parameter('id', Parameter::TYPE_INT),
+        'username' => new StringType('username', 32, true, NULL),
+        'email' => new StringType('email', 64, true, NULL),
+        'password' => new StringType('password', -1, true, NULL),
+        'groups' => new Parameter('groups', Parameter::TYPE_ARRAY, true, NULL),
+      ));
+
+      $this->requiredGroup = array(USER_GROUP_ADMIN);
+      $this->loginRequired = true;
+    }
+
+    public function execute($values = array()) {
+      if (!parent::execute($values)) {
+        return false;
+      }
+
+      $id = $this->getParam("id");
+      $user = $this->getUser($id);
+
+      if ($this->success) {
+        if (empty($user)) {
+          return $this->createError("User not found");
+        }
+
+        $username = $this->getParam("username");
+        $email = $this->getParam("email");
+        $password = $this->getParam("password");
+        $groups = $this->getParam("groups");
+
+        if (!is_null($groups)) {
+          if ($id === $this->user->getId() && !in_array(USER_GROUP_ADMIN, $groups)) {
+            return $this->createError("Cannot remove Administrator group from own user.");
+          }
+        }
+
+        // Check for duplicate username, email
+        $usernameChanged = !is_null($username) ? strcasecmp($username, $this->user->getUsername()) !== 0 : false;
+        $emailChanged = !is_null($email) ? strcasecmp($email, $this->user->getEmail()) !== 0 : false;
+        if($usernameChanged || $emailChanged) {
+          if (!$this->userExists($usernameChanged ? $username : NULL, $emailChanged ? $email : NULL)) {
+            return false;
+          }
+        }
+
+        $sql = $this->user->getSQL();
+        $query = $sql->update("User");
+
+        if ($usernameChanged) $query->set("name", $username);
+        if ($emailChanged) $query->set("email", $email);
+        if (!is_null($password)) $query->set("password", $this->hashPassword($password, $user[0]["salt"]));
+
+        $query->where(new Compare("User.uid", $id));
+        $res = $query->execute();
+        $this->lastError = $sql->getLastError();
+        $this->success = ($res !== FALSE);
+
+        if ($this->success && !is_null($groups)) {
+
+          $deleteQuery = $sql->delete("UserGroup")->where(new Compare("user_id", $id));
+          $insertQuery = $sql->insert("UserGroup", array("user_id", "group_id"));
+
+          foreach($groups as $groupId) {
+            $insertQuery->addRow(array($id, $groupId));
+          }
+
+          $this->success = ($deleteQuery->execute() !== FALSE) && ($insertQuery->execute() !== FALSE);
+          $this->lastError = $sql->getLastError();
+        }
+      }
+
+      return $this->success;
+    }
+  }
 }
\ No newline at end of file
diff --git a/core/Objects/User.class.php b/core/Objects/User.class.php
index 973e948..a2cff62 100644
--- a/core/Objects/User.class.php
+++ b/core/Objects/User.class.php
@@ -20,6 +20,7 @@ class User extends ApiObject {
   private ?Session $session;
   private int $uid;
   private string $username;
+  private string $email;
   private Language $language;
   private array $groups;
 
@@ -50,6 +51,7 @@ class User extends ApiObject {
   public function getId() { return $this->uid; }
   public function isLoggedIn() { return $this->loggedIn; }
   public function getUsername() { return $this->username; }
+  public function getEmail() { return $this->email; }
   public function getSQL() { return $this->sql; }
   public function getLanguage() { return $this->language; }
   public function setLanguage(Language $language) { $this->language = $language; $language->load(); }
@@ -77,6 +79,7 @@ class User extends ApiObject {
       return array(
         'uid' => $this->uid,
         'name' => $this->username,
+        'email' => $this->email,
         'groups' => $this->groups,
         'language' => $this->language->jsonSerialize(),
         'session' => $this->session->jsonSerialize(),
@@ -91,6 +94,7 @@ class User extends ApiObject {
   private function reset() {
     $this->uid = 0;
     $this->username = '';
+    $this->email = '';
     $this->loggedIn = false;
     $this->session = null;
   }
@@ -125,7 +129,8 @@ class User extends ApiObject {
 
   public function readData($userId, $sessionId, $sessionUpdate = true) {
 
-    $res = $this->sql->select("User.name", "Language.uid as langId", "Language.code as langCode", "Language.name as langName",
+    $res = $this->sql->select("User.name", "User.email",
+        "Language.uid as langId", "Language.code as langCode", "Language.name as langName",
         "Session.data", "Session.stay_logged_in", "Session.csrf_token", "Group.uid as groupId", "Group.name as groupName")
         ->from("User")
         ->innerJoin("Session", "Session.user_id", "User.uid")
@@ -146,6 +151,7 @@ class User extends ApiObject {
         $row = $res[0];
         $csrfToken = $row["csrf_token"];
         $this->username = $row['name'];
+        $this->email = $row["email"];
         $this->uid = $userId;
         $this->session = new Session($this, $sessionId, $csrfToken);
         $this->session->setData(json_decode($row["data"] ?? '{}'));
@@ -209,7 +215,8 @@ class User extends ApiObject {
     if($this->loggedIn)
       return true;
 
-    $res = $this->sql->select("ApiKey.user_id as uid", "User.name as username", "Language.uid as langId", "Language.code as langCode", "Language.name as langName")
+    $res = $this->sql->select("ApiKey.user_id as uid", "User.name", "User.email",
+      "Language.uid as langId", "Language.code as langCode", "Language.name as langName")
       ->from("ApiKey")
       ->innerJoin("User", "ApiKey.user_id", "User.uid")
       ->leftJoin("Language", "User.language_id", "Language.uid")
@@ -225,7 +232,8 @@ class User extends ApiObject {
       } else {
         $row = $res[0];
         $this->uid = $row['uid'];
-        $this->username = $row['username'];
+        $this->username = $row['name'];
+        $this->email = $row['email'];
 
         if(!is_null($row['langId'])) {
           $this->setLanguage(Language::newInstance($row['langId'], $row['langCode'], $row['langName']));