#1026 · E-commerce Tool

Shopify Reorder Calculator

Estimate when to reorder Shopify inventory and how many units to buy based on current stock, daily sales, supplier lead time, and safety stock.

Calculator

Inventory planning inputs
units
units/day
days
units
Ad space

How to use this calculator

  • Enter current sellable inventory.
  • Enter average daily sales.
  • Add supplier lead time in days.
  • Add safety stock to protect against delays or demand spikes.

What the result means

The reorder point shows when inventory should be replenished. If current inventory is near or below this level, stockout risk is rising.

Inventory Days = Current Inventory ÷ Daily Sales. Reorder Point = Daily Sales × Lead Time + Safety Stock.

Inventory planning should be adjusted before holidays, promotions, supplier delays, or sudden demand changes.

Example calculation

With 1,000 units, 28 daily sales, 18-day lead time, and 120 safety stock, reorder point is 624 units and coverage is 35.7 days.

Tips for better results

  • Use recent sales velocity, not lifetime average.
  • Raise safety stock before peak season.
  • Track supplier delay history.
  • Avoid tying too much cash in slow inventory.

FAQ

When should I reorder Shopify inventory?

Reorder when current inventory approaches the reorder point, which combines expected sales during supplier lead time and safety stock.

How much safety stock should a Shopify store keep?

Safety stock often covers 7 to 14 days of demand, but volatile products or unreliable suppliers may require more.

How do I avoid Shopify stockouts?

Track inventory days, supplier lead time, sales velocity, and promotion schedules so purchase orders are placed before stock becomes critical.

What inventory level is healthy for ecommerce?

Many stores aim for 30 to 60 days of inventory, but the right level depends on demand stability, margin, and supplier reliability.

What is reorder point in Shopify inventory planning?

Reorder point is the inventory level where you should place a new order to avoid running out before new stock arrives.

Shopify Reorder Metrics

MetricUse
Inventory DaysEstimated days before stockout.
Reorder PointUnit level that triggers reorder.
Stockout RiskRisk based on coverage versus lead time.

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