diff --git a/database/2023_07_21_121854_update_user_agent_storage.php b/database/2023_07_21_121854_update_user_agent_storage.php
new file mode 100644
index 0000000..2d41ecb
--- /dev/null
+++ b/database/2023_07_21_121854_update_user_agent_storage.php
@@ -0,0 +1,51 @@
+<?php
+use Index\Data\IDbConnection;
+use Index\Data\Migration\IDbMigration;
+use Misuzu\ClientInfo;
+
+final class UpdateUserAgentStorage_20230721_121854 implements IDbMigration {
+    public function migrate(IDbConnection $conn): void {
+        // convert user agent fields to BLOB and add field for client info storage
+        $conn->execute('
+            ALTER TABLE msz_login_attempts
+                CHANGE COLUMN attempt_user_agent attempt_user_agent TEXT NOT NULL COLLATE "utf8mb4_bin" AFTER attempt_created,
+                ADD COLUMN attempt_client_info TEXT NULL DEFAULT NULL AFTER attempt_user_agent
+        ');
+        $conn->execute('
+            ALTER TABLE msz_sessions
+                CHANGE column session_user_agent session_user_agent TEXT NOT NULL COLLATE "utf8mb4_bin" AFTER session_ip_last,
+                ADD COLUMN session_client_info TEXT NULL DEFAULT NULL AFTER session_user_agent
+        ');
+
+        // make sure all existing fields have client info fields filled
+        $updateLoginAttempts = $conn->prepare('UPDATE msz_login_attempts SET attempt_client_info = ? WHERE attempt_user_agent = ?');
+        $selectLoginAttempts = $conn->query('SELECT DISTINCT attempt_user_agent FROM msz_login_attempts');
+        while($selectLoginAttempts->next()) {
+            $updateLoginAttempts->reset();
+            $userAgent = $selectLoginAttempts->getString(0);
+            $updateLoginAttempts->addParameter(1, ClientInfo::parse($userAgent)->encode());
+            $updateLoginAttempts->addParameter(2, $userAgent);
+            $updateLoginAttempts->execute();
+        }
+
+        $updateSessions = $conn->prepare('UPDATE msz_sessions SET session_client_info = ? WHERE session_user_agent = ?');
+        $selectSessions = $conn->query('SELECT DISTINCT session_user_agent FROM msz_sessions');
+        while($selectSessions->next()) {
+            $updateSessions->reset();
+            $userAgent = $selectSessions->getString(0);
+            $updateSessions->addParameter(1, ClientInfo::parse($userAgent)->encode());
+            $updateSessions->addParameter(2, $userAgent);
+            $updateSessions->execute();
+        }
+
+        // make client info fields NOT NULL
+        $conn->execute('
+            ALTER TABLE msz_login_attempts
+                CHANGE COLUMN attempt_client_info attempt_client_info TEXT NOT NULL COLLATE "utf8mb4_bin" AFTER attempt_user_agent
+        ');
+        $conn->execute('
+            ALTER TABLE msz_sessions
+                CHANGE COLUMN session_client_info session_client_info TEXT NOT NULL COLLATE "utf8mb4_bin" AFTER session_user_agent
+        ');
+    }
+}
diff --git a/public/index.php b/public/index.php
index a9182f7..7070456 100644
--- a/public/index.php
+++ b/public/index.php
@@ -2,7 +2,9 @@
 namespace Misuzu;
 
 use Misuzu\Users\User;
+use Misuzu\Users\UserNotFoundException;
 use Misuzu\Users\UserSession;
+use Misuzu\Users\UserSessionNotFoundException;
 
 require_once __DIR__ . '/../misuzu.php';
 
diff --git a/src/ClientInfo.php b/src/ClientInfo.php
index dca7fcc..3ba7688 100644
--- a/src/ClientInfo.php
+++ b/src/ClientInfo.php
@@ -1,44 +1,45 @@
 <?php
 namespace Misuzu;
 
-use InvalidArgumentException;
+use stdClass;
+use RuntimeException;
 use Stringable;
 use DeviceDetector\ClientHints;
 use DeviceDetector\DeviceDetector;
 
 class ClientInfo implements Stringable {
-    private DeviceDetector $dd;
+    private const SERIALIZE_VERSION = 1;
 
-    public function __construct(DeviceDetector $dd) {
-        $this->dd = $dd;
-    }
+    public function __construct(
+        private array|bool|null $botInfo,
+        private ?array $clientInfo,
+        private ?array $osInfo,
+        private string $brandName,
+        private string $modelName
+    ) {}
 
     public function __toString(): string {
-        if($this->dd->isBot()) {
-            $botInfo = $this->dd->getBot();
-            return $botInfo['name'] ?? 'an unknown bot';
+        if($this->botInfo === true || is_array($this->botInfo)) {
+            if($this->botInfo === true)
+                return 'a bot';
+            return $this->botInfo['name'] ?? 'an unknown bot';
         }
 
-        $clientInfo = $this->dd->getClient();
-        if(empty($clientInfo['name']))
+        if(empty($this->clientInfo['name']))
             return 'an unknown browser';
 
-        $string = $clientInfo['name'];
-        if(!empty($clientInfo['version']))
-            $string .= ' ' . $clientInfo['version'];
+        $string = $this->clientInfo['name'];
+        if(!empty($this->clientInfo['version']))
+            $string .= ' ' . $this->clientInfo['version'];
 
-        $osInfo = $this->dd->getOs();
-        $hasOsInfo = !empty($osInfo['name']);
-
-        $brandName = $this->dd->getBrandName();
-        $modelName = $this->dd->getModel();
-        $hasModelName = !empty($modelName);
+        $hasOsInfo = !empty($this->osInfo['name']);
+        $hasModelName = !empty($this->modelName);
 
         if($hasOsInfo || $hasModelName)
             $string .= ' on ';
 
         if($hasModelName) {
-            $deviceName = trim($brandName . ' ' . $modelName);
+            $deviceName = trim($this->brandName . ' ' . $this->modelName);
             // most naive check in the world but it works well enough for this lol
             $firstCharIsVowel = in_array(strtolower($deviceName[0]), ['a', 'i', 'u', 'e', 'o']);
             $string .= ($firstCharIsVowel ? 'an' : 'a') . ' ' . $deviceName;
@@ -48,29 +49,71 @@ class ClientInfo implements Stringable {
             if($hasModelName)
                 $string .= ' running ';
 
-            $string .= $osInfo['name'];
-            if(!empty($osInfo['version']))
-                $string .= ' ' . $osInfo['version'];
-            if(!empty($osInfo['platform']))
-                $string .= ' (' . $osInfo['platform'] . ')';
+            $string .= $this->osInfo['name'];
+            if(!empty($this->osInfo['version']))
+                $string .= ' ' . $this->osInfo['version'];
+            if(!empty($this->osInfo['platform']))
+                $string .= ' (' . $this->osInfo['platform'] . ')';
         }
 
         return $string;
     }
 
+    public function encode(): string {
+        $data = new stdClass;
+        $data->version = self::SERIALIZE_VERSION;
+
+        if($this->botInfo === true || is_array($this->botInfo))
+            $data->bot = $this->botInfo;
+        if($this->clientInfo !== null)
+            $data->client = $this->clientInfo;
+        if($this->osInfo !== null)
+            $data->os = $this->osInfo;
+        if($this->brandName !== '')
+            $data->vendor = $this->brandName;
+        if($this->modelName !== '')
+            $data->model = $this->modelName;
+
+        return json_encode($data);
+    }
+
+    public static function decode(string $encoded): self {
+        $data = json_decode($encoded, true);
+        $version = $data['version'] ?? 0;
+        if($version < 0 || $version > self::SERIALIZE_VERSION)
+            throw new RuntimeException('$data does not contain a valid version argument');
+
+        return new static(
+            $data['bot'] ?? null,
+            $data['client'] ?? null,
+            $data['os'] ?? null,
+            $data['vendor'] ?? '',
+            $data['model'] ?? ''
+        );
+    }
+
     public static function parse(array|string $serverVarsOrUserAgent): self {
+        static $dd = null;
+        $dd ??= new DeviceDetector();
+
         if(is_string($serverVarsOrUserAgent)) {
-            $userAgent = $serverVarsOrUserAgent;
-            $clientHints = null;
+            $dd->setUserAgent($serverVarsOrUserAgent);
         } else {
-            $userAgent = array_key_exists('HTTP_USER_AGENT', $serverVarsOrUserAgent)
-                ? $serverVarsOrUserAgent['HTTP_USER_AGENT'] : '';
-            $clientHints = ClientHints::factory($serverVarsOrUserAgent);
+            $dd->setUserAgent(
+                array_key_exists('HTTP_USER_AGENT', $serverVarsOrUserAgent)
+                    ? $serverVarsOrUserAgent['HTTP_USER_AGENT'] : ''
+            );
+            $dd->setClientHints(ClientHints::factory($serverVarsOrUserAgent));
         }
 
-        $dd = new DeviceDetector($userAgent, $clientHints);
         $dd->parse();
 
-        return new static($dd);
+        return new static(
+            $dd->getBot(),
+            $dd->getClient(),
+            $dd->getOs(),
+            $dd->getBrandName(),
+            $dd->getModel()
+        );
     }
 }
diff --git a/src/Users/UserLoginAttempt.php b/src/Users/UserLoginAttempt.php
index b67666d..ba55399 100644
--- a/src/Users/UserLoginAttempt.php
+++ b/src/Users/UserLoginAttempt.php
@@ -13,13 +13,14 @@ class UserLoginAttempt {
     private $attempt_country = 'XX';
     private $attempt_created = null;
     private $attempt_user_agent = '';
+    private $attempt_client_info = '';
 
     private $user = null;
     private $userLookedUp = false;
 
     public const TABLE = 'login_attempts';
     private const QUERY_SELECT = 'SELECT %1$s FROM `' . DB::PREFIX . self::TABLE . '` AS '. self::TABLE;
-    private const SELECT = '%1$s.`user_id`, %1$s.`attempt_success`, %1$s.`attempt_country`, %1$s.`attempt_user_agent`'
+    private const SELECT = '%1$s.`user_id`, %1$s.`attempt_success`, %1$s.`attempt_country`, %1$s.`attempt_user_agent`, %1$s.`attempt_client_info`'
         . ', INET6_NTOA(%1$s.`attempt_ip`) AS `attempt_ip`'
         . ', UNIX_TIMESTAMP(%1$s.`attempt_created`) AS `attempt_created`';
 
@@ -58,8 +59,8 @@ class UserLoginAttempt {
     public function getUserAgent(): string {
         return $this->attempt_user_agent;
     }
-    public function getClientString(): string {
-        return (string)ClientInfo::parse($this->attempt_user_agent);
+    public function getClientInfo(): ClientInfo {
+        return ClientInfo::decode($this->attempt_client_info);
     }
 
     public static function remaining(string $remoteAddr): int {
@@ -78,18 +79,21 @@ class UserLoginAttempt {
         string $countryCode,
         bool $success,
         ?User $user = null,
-        string $userAgent = null
+        string $userAgent = null,
+        ?ClientInfo $clientInfo = null
     ): void {
         $userAgent = $userAgent ?? filter_input(INPUT_SERVER, 'HTTP_USER_AGENT') ?? '';
+        $clientInfo ??= ClientInfo::parse($_SERVER);
 
         $createLog = DB::prepare(
-            'INSERT INTO `' . DB::PREFIX . self::TABLE . '` (`user_id`, `attempt_success`, `attempt_ip`, `attempt_country`, `attempt_user_agent`)'
-            . ' VALUES (:user, :success, INET6_ATON(:ip), :country, :user_agent)'
+            'INSERT INTO `' . DB::PREFIX . self::TABLE . '` (`user_id`, `attempt_success`, `attempt_ip`, `attempt_country`, `attempt_user_agent`, `attempt_client_info`)'
+            . ' VALUES (:user, :success, INET6_ATON(:ip), :country, :user_agent, :client_info)'
         )   ->bind('user', $user === null ? null : $user->getId()) // this null situation should never ever happen but better safe than sorry !
             ->bind('success', $success ? 1 : 0)
             ->bind('ip', $remoteAddr)
             ->bind('country', $countryCode)
             ->bind('user_agent', $userAgent)
+            ->bind('client_info', $clientInfo->encode())
             ->execute();
     }
 
diff --git a/src/Users/UserSession.php b/src/Users/UserSession.php
index f24c576..7a83063 100644
--- a/src/Users/UserSession.php
+++ b/src/Users/UserSession.php
@@ -20,6 +20,7 @@ class UserSession {
     private $session_ip = '::1';
     private $session_ip_last = null;
     private $session_user_agent = '';
+    private $session_client_info = '';
     private $session_country = 'XX';
     private $session_expires = null;
     private $session_expires_bump = 1;
@@ -32,7 +33,7 @@ class UserSession {
 
     public const TABLE = 'sessions';
     private const QUERY_SELECT = 'SELECT %1$s FROM `' . DB::PREFIX . self::TABLE . '` AS '. self::TABLE;
-    private const SELECT = '%1$s.`session_id`, %1$s.`user_id`, %1$s.`session_key`, %1$s.`session_user_agent`, %1$s.`session_country`, %1$s.`session_expires_bump`'
+    private const SELECT = '%1$s.`session_id`, %1$s.`user_id`, %1$s.`session_key`, %1$s.`session_user_agent`, %1$s.`session_client_info`, %1$s.`session_country`, %1$s.`session_expires_bump`'
         . ', INET6_NTOA(%1$s.`session_ip`) AS `session_ip`'
         . ', INET6_NTOA(%1$s.`session_ip_last`) AS `session_ip_last`'
         . ', UNIX_TIMESTAMP(%1$s.`session_created`) AS `session_created`'
@@ -74,8 +75,8 @@ class UserSession {
     public function getUserAgent(): string {
         return $this->session_user_agent;
     }
-    public function getClientString(): string {
-        return (string)ClientInfo::parse($this->session_user_agent);
+    public function getClientInfo(): ClientInfo {
+        return ClientInfo::decode($this->session_client_info);
     }
 
     public function getCountry(): string {
@@ -170,18 +171,26 @@ class UserSession {
             ->execute();
     }
 
-    public static function create(User $user, string $remoteAddr, string $countryCode, ?string $userAgent = null, ?string $token = null): self {
+    public static function create(
+        User $user,
+        string $remoteAddr,
+        string $countryCode,
+        ?string $userAgent = null,
+        ?ClientInfo $clientInfo = null
+    ): self {
         $userAgent = $userAgent ?? filter_input(INPUT_SERVER, 'HTTP_USER_AGENT') ?? '';
-        $token = $token ?? self::generateToken();
+        $clientInfo ??= ClientInfo::parse($_SERVER);
+        $token = self::generateToken();
 
         $sessionId = DB::prepare(
             'INSERT INTO `' . DB::PREFIX . self::TABLE . '`'
-            . ' (`user_id`, `session_ip`, `session_country`, `session_user_agent`, `session_key`, `session_created`, `session_expires`)'
-            . ' VALUES (:user, INET6_ATON(:remote_addr), :country, :user_agent, :token, NOW(), NOW() + INTERVAL :expires SECOND)'
+            . ' (`user_id`, `session_ip`, `session_country`, `session_user_agent`, `session_client_info`, `session_key`, `session_created`, `session_expires`)'
+            . ' VALUES (:user, INET6_ATON(:remote_addr), :country, :user_agent, :client_info, :token, NOW(), NOW() + INTERVAL :expires SECOND)'
         )   ->bind('user', $user->getId())
             ->bind('remote_addr', $remoteAddr)
             ->bind('country', $countryCode)
             ->bind('user_agent', $userAgent)
+            ->bind('client_info', $clientInfo->encode())
             ->bind('token', $token)
             ->bind('expires', self::LIFETIME)
             ->executeGetId();
diff --git a/templates/user/macros.twig b/templates/user/macros.twig
index a338a04..95d93c1 100644
--- a/templates/user/macros.twig
+++ b/templates/user/macros.twig
@@ -73,7 +73,7 @@
                 <div class="flag flag--{{ session.country|lower }} settings__session__flag" title="{{ session.countryName }}">{{ session.country }}</div>
 
                 <div class="settings__session__description">
-                    {{ session.clientString }}
+                    {{ session.clientInfo }}
                 </div>
 
                 <form class="settings__session__actions" method="post" action="{{ url('settings-sessions') }}">
@@ -160,7 +160,7 @@
                 <div class="flag flag--{{ attempt.country|lower }} settings__login-attempt__flag" title="{{ attempt.countryName }}">{{ attempt.country }}</div>
 
                 <div class="settings__login-attempt__description">
-                    {{ attempt.clientString }}
+                    {{ attempt.clientInfo }}
                 </div>
             </div>