diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 7e7a650..7b473d1 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -225,6 +225,44 @@ jobs:
           prerelease: false
           args: ${{ matrix.args }}
 
+      - name: Create portable Windows ZIP
+        if: matrix.platform == 'windows-latest'
+        shell: bash
+        env:
+          TAG: ${{ github.ref_name }}
+        run: |
+          VERSION="${TAG#v}"
+          PORTABLE_DIR="Donut-Portable"
+          mkdir -p "$PORTABLE_DIR"
+
+          # Copy main executable
+          cp "src-tauri/target/${{ matrix.target }}/release/Donut.exe" "$PORTABLE_DIR/"
+
+          # Copy sidecar binaries
+          cp "src-tauri/target/${{ matrix.target }}/release/donut-proxy.exe" "$PORTABLE_DIR/"
+          cp "src-tauri/target/${{ matrix.target }}/release/donut-daemon.exe" "$PORTABLE_DIR/"
+
+          # Copy WebView2Loader if present
+          if [ -f "src-tauri/target/${{ matrix.target }}/release/WebView2Loader.dll" ]; then
+            cp "src-tauri/target/${{ matrix.target }}/release/WebView2Loader.dll" "$PORTABLE_DIR/"
+          fi
+
+          # Create .portable marker
+          touch "$PORTABLE_DIR/.portable"
+
+          # Create ZIP
+          7z a "Donut_${VERSION}_x64-portable.zip" "$PORTABLE_DIR"
+
+      - name: Upload portable ZIP to release
+        if: matrix.platform == 'windows-latest'
+        shell: bash
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          TAG: ${{ github.ref_name }}
+        run: |
+          VERSION="${TAG#v}"
+          gh release upload "$TAG" "Donut_${VERSION}_x64-portable.zip" --clobber
+
       - name: Clean up Apple certificate
         if: matrix.platform == 'macos-latest' && always()
         run: |
@@ -346,7 +384,7 @@ jobs:
 
           ### Windows
 
-          [Download Windows Installer (x64)](${BASE}/Donut_${VERSION}_x64-setup.exe)
+          [Download Windows Installer (x64)](${BASE}/Donut_${VERSION}_x64-setup.exe) · [Portable (x64)](${BASE}/Donut_${VERSION}_x64-portable.zip)
 
           ### Linux
 
diff --git a/.github/workflows/rolling-release.yml b/.github/workflows/rolling-release.yml
index db552d6..b9fe8cc 100644
--- a/.github/workflows/rolling-release.yml
+++ b/.github/workflows/rolling-release.yml
@@ -235,6 +235,34 @@ jobs:
           prerelease: true
           args: ${{ matrix.args }}
 
+      - name: Create portable Windows ZIP
+        if: matrix.platform == 'windows-latest'
+        shell: bash
+        run: |
+          PORTABLE_DIR="Donut-Portable"
+          mkdir -p "$PORTABLE_DIR"
+
+          cp "src-tauri/target/${{ matrix.target }}/release/Donut.exe" "$PORTABLE_DIR/"
+          cp "src-tauri/target/${{ matrix.target }}/release/donut-proxy.exe" "$PORTABLE_DIR/"
+          cp "src-tauri/target/${{ matrix.target }}/release/donut-daemon.exe" "$PORTABLE_DIR/"
+
+          if [ -f "src-tauri/target/${{ matrix.target }}/release/WebView2Loader.dll" ]; then
+            cp "src-tauri/target/${{ matrix.target }}/release/WebView2Loader.dll" "$PORTABLE_DIR/"
+          fi
+
+          touch "$PORTABLE_DIR/.portable"
+
+          7z a "Donut_x64-portable.zip" "$PORTABLE_DIR"
+
+      - name: Upload portable ZIP to release
+        if: matrix.platform == 'windows-latest'
+        shell: bash
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          NIGHTLY_TAG: "nightly-${{ steps.timestamp.outputs.timestamp }}"
+        run: |
+          gh release upload "$NIGHTLY_TAG" "Donut_x64-portable.zip" --clobber
+
       - name: Clean up Apple certificate
         if: matrix.platform == 'macos-latest' && always()
         run: |
diff --git a/src-tauri/src/app_auto_updater.rs b/src-tauri/src/app_auto_updater.rs
index c7b0472..392b75e 100644
--- a/src-tauri/src/app_auto_updater.rs
+++ b/src-tauri/src/app_auto_updater.rs
@@ -1604,6 +1604,10 @@ rm "{}"
 
 #[tauri::command]
 pub async fn check_for_app_updates() -> Result<Option<AppUpdateInfo>, String> {
+  if crate::app_dirs::is_portable() {
+    log::info!("App auto-updates disabled in portable mode");
+    return Ok(None);
+  }
   // The disable_auto_updates setting controls app self-updates only
   let disabled = crate::settings_manager::SettingsManager::instance()
     .load_settings()
diff --git a/src-tauri/src/app_dirs.rs b/src-tauri/src/app_dirs.rs
index 83c4876..7763204 100644
--- a/src-tauri/src/app_dirs.rs
+++ b/src-tauri/src/app_dirs.rs
@@ -3,11 +3,29 @@ use std::path::PathBuf;
 use std::sync::OnceLock;
 
 static BASE_DIRS: OnceLock<BaseDirs> = OnceLock::new();
+static PORTABLE_DIR: OnceLock<Option<PathBuf>> = OnceLock::new();
 
 fn base_dirs() -> &'static BaseDirs {
   BASE_DIRS.get_or_init(|| BaseDirs::new().expect("Failed to get base directories"))
 }
 
+/// Returns the portable base directory if a `.portable` marker exists next to the executable.
+fn portable_dir() -> Option<&'static PathBuf> {
+  PORTABLE_DIR
+    .get_or_init(|| {
+      std::env::current_exe()
+        .ok()
+        .and_then(|exe| exe.parent().map(|p| p.to_path_buf()))
+        .filter(|dir| dir.join(".portable").exists())
+    })
+    .as_ref()
+}
+
+/// Returns true if the app is running in portable mode.
+pub fn is_portable() -> bool {
+  portable_dir().is_some()
+}
+
 pub fn app_name() -> &'static str {
   if cfg!(debug_assertions) {
     "DonutBrowserDev"
@@ -28,6 +46,10 @@ pub fn data_dir() -> PathBuf {
     return PathBuf::from(dir);
   }
 
+  if let Some(dir) = portable_dir() {
+    return dir.join("data");
+  }
+
   base_dirs().data_local_dir().join(app_name())
 }
 
@@ -43,6 +65,10 @@ pub fn cache_dir() -> PathBuf {
     return PathBuf::from(dir);
   }
 
+  if let Some(dir) = portable_dir() {
+    return dir.join("cache");
+  }
+
   base_dirs().cache_dir().join(app_name())
 }
 
diff --git a/src-tauri/src/daemon/autostart.rs b/src-tauri/src/daemon/autostart.rs
index 5973f82..9727f12 100644
--- a/src-tauri/src/daemon/autostart.rs
+++ b/src-tauri/src/daemon/autostart.rs
@@ -340,6 +340,9 @@ pub fn is_autostart_enabled() -> bool {
 }
 
 pub fn get_data_dir() -> Option<PathBuf> {
+  if crate::app_dirs::is_portable() {
+    return Some(crate::app_dirs::data_dir());
+  }
   if let Some(proj_dirs) = ProjectDirs::from("com", "donutbrowser", "Donut Browser") {
     Some(proj_dirs.data_dir().to_path_buf())
   } else {
diff --git a/src-tauri/src/settings_manager.rs b/src-tauri/src/settings_manager.rs
index 459ea43..b239703 100644
--- a/src-tauri/src/settings_manager.rs
+++ b/src-tauri/src/settings_manager.rs
@@ -950,6 +950,7 @@ pub struct SystemInfo {
   pub app_version: String,
   pub os: String,
   pub arch: String,
+  pub portable: bool,
 }
 
 #[tauri::command]
@@ -976,6 +977,7 @@ pub fn get_system_info() -> SystemInfo {
     app_version: crate::app_auto_updater::AppAutoUpdater::get_current_version(),
     os: os.to_string(),
     arch: arch.to_string(),
+    portable: crate::app_dirs::is_portable(),
   }
 }
 
diff --git a/src/components/settings-dialog.tsx b/src/components/settings-dialog.tsx
index 8281304..a30eb79 100644
--- a/src/components/settings-dialog.tsx
+++ b/src/components/settings-dialog.tsx
@@ -128,6 +128,7 @@ export function SettingsDialog({
     app_version: string;
     os: string;
     arch: string;
+    portable: boolean;
   } | null>(null);
 
   const { t } = useTranslation();
@@ -237,6 +238,7 @@ export function SettingsDialog({
           app_version: string;
           os: string;
           arch: string;
+          portable: boolean;
         }>("get_system_info");
         setSystemInfo(info);
       } catch {
@@ -1109,7 +1111,7 @@ export function SettingsDialog({
           {systemInfo && (
             <div className="pt-2 border-t">
               <p className="text-xs text-muted-foreground font-mono whitespace-pre-line select-all">
-                {`Donut Browser ${systemInfo.app_version}\n${systemInfo.os} ${systemInfo.arch}`}
+                {`Donut Browser ${systemInfo.app_version}\n${systemInfo.os} ${systemInfo.arch}${systemInfo.portable ? " (portable)" : ""}`}
               </p>
             </div>
           )}