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The reorder point is the stock level that should trigger your next purchase order: average daily demand × supplier lead time, plus safety stock. Order when inventory crosses this line and the new stock lands just before you'd run out. Calculate yours below.
Don't know your safety stock? Use the safety stock calculator first.
Reorder when stock falls to
330 units
= 280 units expected to sell during the lead time + 50 safety stock
Reorder Point = (d̄ × L) + SS. Once you place an order, you keep selling for the whole lead time — so the trigger has to sit high enough to cover expected sales during the wait (d̄ × L), plus a buffer for demand surprises (safety stock). Reordering at zero means being out of stock for the entire lead time.
Worked example: 20 units/day average, 14-day lead time, 50 units of safety stock → reorder point = 20 × 14 + 50 = 330 units. When stock hits 330, order; the shipment lands around the time you'd otherwise have dipped into the buffer.
All three inputs move: demand accelerates or decays, suppliers slow down in peak season, and buffers set in January are wrong by October. The formula isn't the hard part — keeping it current across hundreds of SKUs is. Yeer recalculates reorder points continuously from your live Shopify data and tells you what to order before you run out — see demand forecasting.
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Reorder Point = (average daily demand × lead time in days) + safety stock. It answers: at what stock level should I place the next order so it arrives before I run out? The first term covers expected sales during the wait; safety stock covers the unexpected.
Safety stock is a buffer quantity you aim never to dip into under normal conditions. The reorder point is a trigger level that includes that buffer: expected lead-time demand plus safety stock. You reorder when inventory hits the trigger, not when it hits zero.
A common starting point is the Economic Order Quantity (EOQ), which balances ordering costs against holding costs — or simpler: enough to cover your target days of stock minus what's arriving. See our EOQ guide for the formula.
Yes — demand rate, variability, and lead time differ per product, so a single store-wide rule guarantees some products stock out while others sit overstocked. This is exactly the calculation tools like Yeer automate per SKU, continuously.
Whenever demand or lead times shift — which for most stores means at least monthly, and weekly in Q4. Static reorder points set in January are a common cause of holiday stockouts. Yeer refreshes them continuously from live sales data.
Yeer watches demand and lead times per product and flags what to reorder before you run out. Free up to 50 products.
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