How to calculate a reorder point for Shopify

Start with demand during lead time

A simple reorder point is average daily demand multiplied by supplier lead time, plus a safety-stock allowance. Use consistent units: units per day, calendar days and units of stock. It is a trigger for reviewing a purchase, not the final purchase quantity.

Worked example: a trigger of 54 units

Illustrative example: a product sells two units per day, takes 21 days to arrive and has 12 units of safety stock. The simple trigger is 2 × 21 + 12 = 54 units. Compare that trigger with a reliable inventory position, including inbound stock only when its timing makes it usable.

The quantity to buy answers a different question

A replenishment quantity also considers the review period, existing stock, dependable inbound quantities and supplier constraints. At two units a day over 35 days, with 12 safety units and 29 available units, the unrounded requirement is 70 + 12 − 29 = 53. A case pack of 12 would round that to 60 before cash and other policies are reviewed.

When the simple formula is not enough

A changing demand pattern, stockout, promotion or uncertain delivery can make a single average misleading. ReOrder makes forecast and policy inputs visible; the calculator on this website is an educational approximation, not the full forecasting engine.

• Check that the history covers a representative period.
• Review stockouts before treating zero recorded sales as zero demand.
• Check open-order arrival dates before counting inbound inventory.
• Review supplier rounding and your buying budget before approving a purchase.

In the ReOrder workflow

ReOrder compares transparent forecasting baselines and selects the one with the lowest rolling backtest error. Visible calculations remain the source of every quantity.

This description shares the maintained content used by the in-app Help Center.

Check the plan with your own store

Start with one Shopify store, confirm the inputs and review every recommendation before acting. The current release supports up to 3,000 variants and reads up to 1,000 recent orders, with warnings for incomplete imports.