diff --git a/includes/Api/OrdersController.php b/includes/Api/OrdersController.php
index 8631265..24eb07b 100644
--- a/includes/Api/OrdersController.php
+++ b/includes/Api/OrdersController.php
@@ -97,6 +97,31 @@ class OrdersController {
         'permission_callback' => function () { return current_user_can('manage_woocommerce'); },
     ]);
 
+    // Calculate shipping rates for given address and cart
+    register_rest_route('woonoow/v1', '/shipping/calculate', [
+        'methods'             => 'POST',
+        'callback'            => [__CLASS__, 'calculate_shipping'],
+        'permission_callback' => function () { return current_user_can('manage_woocommerce'); },
+        'args' => [
+            'items'    => [ 'type' => 'array',  'required' => true ],
+            'shipping' => [ 'type' => 'object', 'required' => true ],
+        ],
+    ]);
+
+    // Calculate order preview with taxes and totals
+    register_rest_route('woonoow/v1', '/orders/preview', [
+        'methods'             => 'POST',
+        'callback'            => [__CLASS__, 'preview_order'],
+        'permission_callback' => function () { return current_user_can('manage_woocommerce'); },
+        'args' => [
+            'items'           => [ 'type' => 'array',  'required' => true ],
+            'billing'         => [ 'type' => 'object', 'required' => false ],
+            'shipping'        => [ 'type' => 'object', 'required' => false ],
+            'shipping_method' => [ 'type' => 'string', 'required' => false ],
+            'coupons'         => [ 'type' => 'array',  'required' => false ],
+        ],
+    ]);
+
     // Retry payment processing for an order
     register_rest_route('woonoow/v1', '/orders/(?P<id>\d+)/retry-payment', [
         'methods'             => 'POST',
@@ -1197,6 +1222,176 @@ class OrdersController {
     return new \WP_REST_Response( $rows, 200 );
   }
 
+  /**
+   * Calculate shipping rates for given cart and address
+   * POST /woonoow/v1/shipping/calculate
+   */
+  public static function calculate_shipping( WP_REST_Request $req ) : \WP_REST_Response {
+    $p = $req->get_json_params();
+    $items = is_array( $p['items'] ?? null ) ? $p['items'] : [];
+    $shipping = is_array( $p['shipping'] ?? null ) ? $p['shipping'] : [];
+
+    if ( empty( $items ) ) {
+      return new \WP_REST_Response( [ 'error' => 'items_required' ], 400 );
+    }
+
+    try {
+      // Create a temporary cart to calculate shipping
+      WC()->cart->empty_cart();
+      
+      // Add items to cart
+      foreach ( $items as $item ) {
+        $product_id = absint( $item['product_id'] ?? 0 );
+        $qty = max( 1, absint( $item['qty'] ?? 1 ) );
+        if ( $product_id ) {
+          WC()->cart->add_to_cart( $product_id, $qty );
+        }
+      }
+
+      // Set customer shipping address
+      if ( ! empty( $shipping ) ) {
+        WC()->customer->set_shipping_country( $shipping['country'] ?? '' );
+        WC()->customer->set_shipping_state( $shipping['state'] ?? '' );
+        WC()->customer->set_shipping_postcode( $shipping['postcode'] ?? '' );
+        WC()->customer->set_shipping_city( $shipping['city'] ?? '' );
+        WC()->customer->set_shipping_address( $shipping['address_1'] ?? '' );
+        WC()->customer->set_shipping_address_2( $shipping['address_2'] ?? '' );
+      }
+
+      // Calculate shipping
+      WC()->cart->calculate_shipping();
+      WC()->cart->calculate_totals();
+
+      // Get available shipping packages and rates
+      $packages = WC()->shipping()->get_packages();
+      $methods = [];
+
+      foreach ( $packages as $package_key => $package ) {
+        $rates = $package['rates'] ?? [];
+        
+        foreach ( $rates as $rate_id => $rate ) {
+          /** @var \WC_Shipping_Rate $rate */
+          $methods[] = [
+            'id' => $rate_id,
+            'method_id' => $rate->get_method_id(),
+            'instance_id' => $rate->get_instance_id(),
+            'label' => $rate->get_label(),
+            'cost' => (float) $rate->get_cost(),
+            'taxes' => $rate->get_taxes(),
+            'meta_data' => $rate->get_meta_data(),
+          ];
+        }
+      }
+
+      // Clean up
+      WC()->cart->empty_cart();
+
+      return new \WP_REST_Response( [
+        'methods' => $methods,
+        'has_methods' => ! empty( $methods ),
+      ], 200 );
+
+    } catch ( \Throwable $e ) {
+      // Clean up on error
+      WC()->cart->empty_cart();
+      
+      return new \WP_REST_Response( [
+        'error' => 'calculation_failed',
+        'message' => $e->getMessage(),
+      ], 500 );
+    }
+  }
+
+  /**
+   * Preview order totals (subtotal, shipping, tax, total)
+   * POST /woonoow/v1/orders/preview
+   */
+  public static function preview_order( WP_REST_Request $req ) : \WP_REST_Response {
+    $p = $req->get_json_params();
+    $items = is_array( $p['items'] ?? null ) ? $p['items'] : [];
+    $billing = is_array( $p['billing'] ?? null ) ? $p['billing'] : [];
+    $shipping = is_array( $p['shipping'] ?? null ) ? $p['shipping'] : [];
+    $shipping_method = sanitize_text_field( $p['shipping_method'] ?? '' );
+    $coupons = array_filter( array_map( 'sanitize_text_field', (array) ( $p['coupons'] ?? [] ) ) );
+
+    if ( empty( $items ) ) {
+      return new \WP_REST_Response( [ 'error' => 'items_required' ], 400 );
+    }
+
+    try {
+      // Use WooCommerce cart for calculation
+      WC()->cart->empty_cart();
+      
+      // Add items
+      foreach ( $items as $item ) {
+        $product_id = absint( $item['product_id'] ?? 0 );
+        $qty = max( 1, absint( $item['qty'] ?? 1 ) );
+        if ( $product_id ) {
+          WC()->cart->add_to_cart( $product_id, $qty );
+        }
+      }
+
+      // Set customer addresses for tax calculation
+      if ( ! empty( $billing ) ) {
+        WC()->customer->set_billing_country( $billing['country'] ?? '' );
+        WC()->customer->set_billing_state( $billing['state'] ?? '' );
+        WC()->customer->set_billing_postcode( $billing['postcode'] ?? '' );
+        WC()->customer->set_billing_city( $billing['city'] ?? '' );
+      }
+
+      if ( ! empty( $shipping ) ) {
+        WC()->customer->set_shipping_country( $shipping['country'] ?? '' );
+        WC()->customer->set_shipping_state( $shipping['state'] ?? '' );
+        WC()->customer->set_shipping_postcode( $shipping['postcode'] ?? '' );
+        WC()->customer->set_shipping_city( $shipping['city'] ?? '' );
+      }
+
+      // Apply coupons
+      foreach ( $coupons as $code ) {
+        WC()->cart->apply_coupon( $code );
+      }
+
+      // Set chosen shipping method if provided
+      if ( $shipping_method ) {
+        WC()->session->set( 'chosen_shipping_methods', [ $shipping_method ] );
+      }
+
+      // Calculate totals
+      WC()->cart->calculate_shipping();
+      WC()->cart->calculate_totals();
+
+      // Get totals
+      $result = [
+        'subtotal' => (float) WC()->cart->get_subtotal(),
+        'subtotal_tax' => (float) WC()->cart->get_subtotal_tax(),
+        'discount_total' => (float) WC()->cart->get_discount_total(),
+        'discount_tax' => (float) WC()->cart->get_discount_tax(),
+        'shipping_total' => (float) WC()->cart->get_shipping_total(),
+        'shipping_tax' => (float) WC()->cart->get_shipping_tax(),
+        'cart_contents_tax' => (float) WC()->cart->get_cart_contents_tax(),
+        'fee_tax' => (float) WC()->cart->get_fee_tax(),
+        'total_tax' => (float) WC()->cart->get_total_tax(),
+        'total' => (float) WC()->cart->get_total( 'edit' ),
+        'tax_display_cart' => get_option( 'woocommerce_tax_display_cart', 'excl' ),
+        'prices_include_tax' => wc_prices_include_tax(),
+      ];
+
+      // Clean up
+      WC()->cart->empty_cart();
+
+      return new \WP_REST_Response( $result, 200 );
+
+    } catch ( \Throwable $e ) {
+      // Clean up on error
+      WC()->cart->empty_cart();
+      
+      return new \WP_REST_Response( [
+        'error' => 'preview_failed',
+        'message' => $e->getMessage(),
+      ], 500 );
+    }
+  }
+
   public static function countries( WP_REST_Request $req ) : \WP_REST_Response {
     $rows    = [];
     $states  = [];