diff --git a/cmd/adjust-quantity-product-warehouse-from-purchase/main.go b/cmd/adjust-quantity-product-warehouse-from-purchase/main.go
new file mode 100644
index 00000000..2d7ab9fb
--- /dev/null
+++ b/cmd/adjust-quantity-product-warehouse-from-purchase/main.go
@@ -0,0 +1,291 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"log"
+	"math"
+	"os"
+	"strings"
+
+	"gitlab.com/mbugroup/lti-api.git/internal/config"
+	"gitlab.com/mbugroup/lti-api.git/internal/database"
+	entity "gitlab.com/mbugroup/lti-api.git/internal/entities"
+	"gorm.io/gorm"
+)
+
+const (
+	levelAllNoFlagProducts = 1
+	levelProductName       = 2
+	levelProductWarehouse  = 3
+	qtyEpsilon             = 1e-6
+)
+
+type targetRow struct {
+	ProductWarehouseID uint    `gorm:"column:product_warehouse_id"`
+	ProductID          uint    `gorm:"column:product_id"`
+	ProductName        string  `gorm:"column:product_name"`
+	CurrentQty         float64 `gorm:"column:current_qty"`
+	ComputedQty        float64 `gorm:"column:computed_qty"`
+}
+
+func main() {
+	var (
+		level              int
+		productName        string
+		productWarehouseID uint
+		apply              bool
+	)
+
+	flag.IntVar(
+		&level,
+		"level",
+		levelAllNoFlagProducts,
+		"CLI level: 1=all products without flags, 2=specific product name (without flags), 3=specific product warehouse id",
+	)
+	flag.StringVar(&productName, "product-name", "", "Product name (required for level 2)")
+	flag.UintVar(&productWarehouseID, "product-warehouse-id", 0, "Product warehouse id (required for level 3)")
+	flag.BoolVar(&apply, "apply", false, "Apply changes. If false, run as dry-run")
+	flag.Parse()
+
+	productName = strings.TrimSpace(productName)
+	if err := validateFlags(level, productName, productWarehouseID); err != nil {
+		log.Fatalf("invalid flags: %v", err)
+	}
+
+	ctx := context.Background()
+	db := database.Connect(config.DBHost, config.DBName)
+
+	targets, err := loadTargets(ctx, db, level, productName, productWarehouseID)
+	if err != nil {
+		log.Fatalf("failed to load target product warehouses: %v", err)
+	}
+
+	fmt.Printf("Mode: %s\n", modeLabel(apply))
+	fmt.Printf("Level: %d (%s)\n", level, levelLabel(level))
+	if productName != "" {
+		fmt.Printf("Filter product_name: %s\n", productName)
+	}
+	if productWarehouseID > 0 {
+		fmt.Printf("Filter product_warehouse_id: %d\n", productWarehouseID)
+	}
+	fmt.Printf("Targets found: %d\n\n", len(targets))
+
+	if len(targets) == 0 {
+		fmt.Println("No matching product warehouse rows to process")
+		return
+	}
+
+	for _, row := range targets {
+		fmt.Printf(
+			"PLAN pw=%d product_id=%d product=%q current_qty=%.3f computed_qty=%.3f delta=%.3f\n",
+			row.ProductWarehouseID,
+			row.ProductID,
+			row.ProductName,
+			row.CurrentQty,
+			row.ComputedQty,
+			row.ComputedQty-row.CurrentQty,
+		)
+	}
+
+	if !apply {
+		fmt.Println()
+		fmt.Printf("Summary: planned=%d updated=0 skipped=0 failed=0\n", len(targets))
+		return
+	}
+
+	updated := 0
+	skipped := 0
+	err = db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		for _, row := range targets {
+			if nearlyEqual(row.CurrentQty, row.ComputedQty) {
+				fmt.Printf(
+					"SKIP pw=%d reason=no_change current_qty=%.3f computed_qty=%.3f\n",
+					row.ProductWarehouseID,
+					row.CurrentQty,
+					row.ComputedQty,
+				)
+				skipped++
+				continue
+			}
+
+			if err := tx.Table("product_warehouses").
+				Where("id = ?", row.ProductWarehouseID).
+				Update("qty", row.ComputedQty).Error; err != nil {
+				return fmt.Errorf("update qty for product_warehouse_id=%d: %w", row.ProductWarehouseID, err)
+			}
+
+			fmt.Printf(
+				"DONE pw=%d product_id=%d product=%q old_qty=%.3f new_qty=%.3f\n",
+				row.ProductWarehouseID,
+				row.ProductID,
+				row.ProductName,
+				row.CurrentQty,
+				row.ComputedQty,
+			)
+			updated++
+		}
+		return nil
+	})
+	if err != nil {
+		fmt.Println()
+		fmt.Printf("Summary: planned=%d updated=%d skipped=%d failed=1\n", len(targets), updated, skipped)
+		log.Printf("error: %v", err)
+		os.Exit(1)
+	}
+
+	fmt.Println()
+	fmt.Printf("Summary: planned=%d updated=%d skipped=%d failed=0\n", len(targets), updated, skipped)
+}
+
+func validateFlags(level int, productName string, productWarehouseID uint) error {
+	switch level {
+	case levelAllNoFlagProducts:
+		if productName != "" {
+			return errors.New("--product-name cannot be used on level 1")
+		}
+		if productWarehouseID > 0 {
+			return errors.New("--product-warehouse-id cannot be used on level 1")
+		}
+	case levelProductName:
+		if productName == "" {
+			return errors.New("--product-name is required on level 2")
+		}
+		if productWarehouseID > 0 {
+			return errors.New("--product-warehouse-id cannot be used on level 2")
+		}
+	case levelProductWarehouse:
+		if productWarehouseID == 0 {
+			return errors.New("--product-warehouse-id is required on level 3")
+		}
+		if productName != "" {
+			return errors.New("--product-name cannot be used on level 3")
+		}
+	default:
+		return fmt.Errorf("unsupported --level=%d (allowed: 1, 2, 3)", level)
+	}
+
+	return nil
+}
+
+func loadTargets(
+	ctx context.Context,
+	db *gorm.DB,
+	level int,
+	productName string,
+	productWarehouseID uint,
+) ([]targetRow, error) {
+	switch level {
+	case levelAllNoFlagProducts:
+		return loadTargetsLevel1ByProductWithoutFlags(ctx, db)
+	case levelProductName:
+		return loadTargetsLevel2ByProductWarehouseWithoutFlags(ctx, db, productName)
+	case levelProductWarehouse:
+		return loadTargetByProductWarehouseID(ctx, db, productWarehouseID)
+	default:
+		return nil, fmt.Errorf("unsupported level %d", level)
+	}
+}
+
+func loadTargetsLevel1ByProductWithoutFlags(ctx context.Context, db *gorm.DB) ([]targetRow, error) {
+	rows := make([]targetRow, 0)
+	if err := db.WithContext(ctx).
+		Table("product_warehouses pw").
+		Select(`
+			pw.id AS product_warehouse_id,
+			pw.product_id AS product_id,
+			p.name AS product_name,
+			COALESCE(pw.qty, 0) AS current_qty,
+			COALESCE(SUM(pi.total_qty), 0) AS computed_qty
+		`).
+		Joins("JOIN products p ON p.id = pw.product_id").
+		Joins("LEFT JOIN flags f ON f.flagable_id = p.id AND f.flagable_type = ?", entity.FlagableTypeProduct).
+		Joins("LEFT JOIN purchase_items pi ON pi.product_warehouse_id = pw.id").
+		Where("p.deleted_at IS NULL").
+		Where("f.id IS NULL").
+		Group("pw.id, pw.product_id, p.name, pw.qty").
+		Order("pw.id ASC").
+		Scan(&rows).Error; err != nil {
+		return nil, err
+	}
+
+	return rows, nil
+}
+
+func loadTargetsLevel2ByProductWarehouseWithoutFlags(
+	ctx context.Context,
+	db *gorm.DB,
+	productName string,
+) ([]targetRow, error) {
+	rows := make([]targetRow, 0)
+	if err := db.WithContext(ctx).
+		Table("product_warehouses pw").
+		Select(`
+			pw.id AS product_warehouse_id,
+			pw.product_id AS product_id,
+			p.name AS product_name,
+			COALESCE(pw.qty, 0) AS current_qty,
+			COALESCE(SUM(pi.total_qty), 0) AS computed_qty
+		`).
+		Joins("JOIN products p ON p.id = pw.product_id").
+		Joins("LEFT JOIN flags f ON f.flagable_id = p.id AND f.flagable_type = ?", entity.FlagableTypeProduct).
+		Joins("LEFT JOIN purchase_items pi ON pi.product_warehouse_id = pw.id").
+		Where("p.deleted_at IS NULL").
+		Where("f.id IS NULL").
+		Where("LOWER(p.name) = LOWER(?)", productName).
+		Group("pw.id, pw.product_id, p.name, pw.qty").
+		Order("pw.id ASC").
+		Scan(&rows).Error; err != nil {
+		return nil, err
+	}
+
+	return rows, nil
+}
+
+func loadTargetByProductWarehouseID(ctx context.Context, db *gorm.DB, productWarehouseID uint) ([]targetRow, error) {
+	rows := make([]targetRow, 0)
+	if err := db.WithContext(ctx).
+		Table("product_warehouses pw").
+		Select(`
+			pw.id AS product_warehouse_id,
+			pw.product_id AS product_id,
+			p.name AS product_name,
+			COALESCE(pw.qty, 0) AS current_qty,
+			COALESCE(SUM(pi.total_qty), 0) AS computed_qty
+		`).
+		Joins("JOIN products p ON p.id = pw.product_id").
+		Joins("LEFT JOIN purchase_items pi ON pi.product_warehouse_id = pw.id").
+		Where("pw.id = ?", productWarehouseID).
+		Group("pw.id, pw.product_id, p.name, pw.qty").
+		Scan(&rows).Error; err != nil {
+		return nil, err
+	}
+
+	return rows, nil
+}
+
+func modeLabel(apply bool) string {
+	if apply {
+		return "APPLY"
+	}
+	return "DRY-RUN"
+}
+
+func levelLabel(level int) string {
+	switch level {
+	case levelAllNoFlagProducts:
+		return "all products without flags (source: purchase_items by product_warehouse_id)"
+	case levelProductName:
+		return "specific product name without flags (source: purchase_items by product_warehouse_id)"
+	case levelProductWarehouse:
+		return "specific product_warehouse_id (source: purchase_items by product_warehouse_id)"
+	default:
+		return "unknown"
+	}
+}
+
+func nearlyEqual(a, b float64) bool {
+	return math.Abs(a-b) <= qtyEpsilon
+}