diff --git a/app/Http/Controllers/ProfileController.php b/app/Http/Controllers/ProfileController.php
index 049ddb1..f839a32 100644
--- a/app/Http/Controllers/ProfileController.php
+++ b/app/Http/Controllers/ProfileController.php
@@ -9,9 +9,11 @@ use Illuminate\Support\Facades\Auth;
 use Illuminate\Support\Facades\Redirect;
 use Illuminate\Support\Facades\Storage;
 use Illuminate\View\View;
+use App\Traits\ImageHandler;
 
 class ProfileController extends Controller
 {
+    use ImageHandler;
     /**
      * Display the user's profile form.
      */
@@ -48,7 +50,7 @@ class ProfileController extends Controller
     public function updateAvatar(Request $request): \Illuminate\Http\JsonResponse
     {
         $request->validate([
-            'avatar' => ['required', 'image', 'mimes:jpeg,png,jpg,gif,webp', 'max:1024'],
+            'avatar' => ['required', 'image', 'mimes:jpeg,png,jpg,gif,webp', 'max:5120'],
         ]);
 
         $user = $request->user();
@@ -59,7 +61,8 @@ class ProfileController extends Controller
                 Storage::disk('public')->delete($user->avatar);
             }
 
-            $path = $request->file('avatar')->store('avatars', 'public');
+            // 將上傳的大頭貼轉換為高壓縮率且清晰的 WebP 格式 (300x300 居中裁切)
+            $path = $this->storeAsWebp($request->file('avatar'), 'avatars', 85, 300, 300);
             $user->avatar = $path;
             $user->save();
 
diff --git a/app/Http/Requests/ProfileUpdateRequest.php b/app/Http/Requests/ProfileUpdateRequest.php
index f4a10f8..9e5ded7 100644
--- a/app/Http/Requests/ProfileUpdateRequest.php
+++ b/app/Http/Requests/ProfileUpdateRequest.php
@@ -19,7 +19,7 @@ class ProfileUpdateRequest extends FormRequest
             'name' => ['required', 'string', 'max:255'],
             'email' => ['required', 'string', 'lowercase', 'email', 'max:255', Rule::unique(User::class)->ignore($this->user()->id)],
             'phone' => ['nullable', 'string', 'max:20'],
-            'avatar' => ['nullable', 'image', 'mimes:jpeg,png,jpg,gif', 'max:2048'],
+            'avatar' => ['nullable', 'image', 'mimes:jpeg,png,jpg,gif,webp', 'max:5120'],
         ];
     }
 }
diff --git a/lang/en.json b/lang/en.json
index 447b741..0b6003e 100644
--- a/lang/en.json
+++ b/lang/en.json
@@ -1616,6 +1616,7 @@
     "The Super Admin role is immutable.": "The Super Admin role is immutable.",
     "The Super Admin role name cannot be modified.": "The Super Admin role name cannot be modified.",
     "The image is too large. Please upload an image smaller than 1MB.": "The image is too large. Please upload an image smaller than 1MB.",
+    "The image is too large. Please upload an image smaller than 5MB.": "The image is too large. Please upload an image smaller than 5MB.",
     "This is a system administrator role. Its name is locked to ensure system stability.": "This is a system administrator role. Its name is locked to ensure system stability.",
     "This machine has a pending command. Please wait.": "This machine has a pending command. Please wait.",
     "This role belongs to another company and cannot be assigned.": "This role belongs to another company and cannot be assigned.",
diff --git a/lang/ja.json b/lang/ja.json
index 2c012c2..af811ed 100644
--- a/lang/ja.json
+++ b/lang/ja.json
@@ -1616,6 +1616,7 @@
     "The Super Admin role is immutable.": "特権管理者ロールは変更できません。",
     "The Super Admin role name cannot be modified.": "特権管理者ロールの名前は変更できません。",
     "The image is too large. Please upload an image smaller than 1MB.": "画像サイズが大きすぎます。1MB未満の画像をアップロードしてください。",
+    "The image is too large. Please upload an image smaller than 5MB.": "画像サイズが大きすぎます。5MB未満の画像をアップロードしてください。",
     "This is a system administrator role. Its name is locked to ensure system stability.": "これはシステム管理者ロールです。システムの安定性を確保するため、名前はロックされています。",
     "This machine has a pending command. Please wait.": "この機器には実行中のコマンドがあります。しばらくお待ちください。",
     "This role belongs to another company and cannot be assigned.": "このロールは別の会社に属しているため、割り当てることができません。",
diff --git a/lang/zh_TW.json b/lang/zh_TW.json
index e55b14a..370fcc9 100644
--- a/lang/zh_TW.json
+++ b/lang/zh_TW.json
@@ -1638,6 +1638,7 @@
     "The Super Admin role is immutable.": "超級管理員角色不可修改。",
     "The Super Admin role name cannot be modified.": "超級管理員角色的名稱無法修改。",
     "The image is too large. Please upload an image smaller than 1MB.": "圖片檔案太大，請上傳小於 1MB 的圖片。",
+    "The image is too large. Please upload an image smaller than 5MB.": "圖片檔案太大，請上傳小於 5MB 的圖片。",
     "This is a system administrator role. Its name is locked to ensure system stability.": "這是系統管理員角色，名稱已鎖定以確保系統穩定性。",
     "This machine has a pending command. Please wait.": "此機台已有指令正在執行，請稍後。",
     "This role belongs to another company and cannot be assigned.": "此角色屬於其他公司，無法指派。",
diff --git a/resources/views/profile/edit.blade.php b/resources/views/profile/edit.blade.php
index 1dbb847..1ee3d4e 100644
--- a/resources/views/profile/edit.blade.php
+++ b/resources/views/profile/edit.blade.php
@@ -8,9 +8,9 @@
                 const file = event.target.files[0];
                 if (!file) return;
                 
-                // Size Check (1MB = 1024 * 1024 bytes)
-                if (file.size > 1024 * 1024) {
-                    alert('{{ __('The image is too large. Please upload an image smaller than 1MB.') }}');
+                // Size Check (5MB = 5 * 1024 * 1024 bytes)
+                if (file.size > 5 * 1024 * 1024) {
+                    alert('{{ __('The image is too large. Please upload an image smaller than 5MB.') }}');
                     return;
                 }