This free reorder level calculator tells you the exact stock level at which to place your next purchase order, so replenishment arrives before you run out. Enter your daily usage, lead time and safety stock for the quick answer — or switch to stock-control mode to also get your minimum, maximum and average stock levels. It works as a reorder point calculator for any raw material, component or finished good.
How to calculate the reorder level
The reorder level (also called the reorder point or ROL) is the demand you expect during the supplier’s lead time, plus a safety buffer:
- Reorder level =
(average daily usage × lead time) + safety stock - Common alternative: reorder level =
maximum daily usage × maximum lead time
Worked example: if you use 100 units a day, your supplier takes 10 days, and you hold 200 units of safety stock, the reorder level is (100 × 10) + 200 = 1,200 units. The moment on-hand stock drops to 1,200, you place the order; the 1,000 units of lead-time demand carry you through the wait, and the 200 units of safety stock protect you if demand runs hot or the delivery is late.
Reorder level, minimum, maximum & average levels
Traditional stock control sets four levels for every item. This calculator’s stock-control mode computes all of them:
| Level | Formula | Purpose |
|---|---|---|
| Reorder level | max usage × max lead time | Triggers a new purchase order. |
| Minimum level | reorder level − (avg usage × avg lead time) | The safety floor you should not breach. |
| Maximum level | reorder level + reorder qty − (min usage × min lead time) | Ceiling that avoids overstocking. |
| Average level | minimum level + (reorder quantity ÷ 2) | Typical stock held; drives carrying cost. |
Setting these four levels per item keeps stock inside a healthy band: you never fall below the minimum (stock-out risk) or rise above the maximum (cash tied up and obsolescence risk).
Reorder level vs safety stock vs EOQ
These three inventory numbers work together but answer different questions. Safety stock is how much buffer to hold against variability. The reorder level is when to order — it adds lead-time demand on top of that buffer. The reorder quantity or EOQ is how much to order each time. Set them together and your purchasing runs on autopilot: order EOQ units whenever stock hits the reorder level, and never dip below safety stock.
From a manual level to automatic reordering
A reorder level calculator gives you one number for one item from figures you type in. In a live factory, usage and lead times shift across hundreds of items, and a static reorder level quickly goes stale. Inside OEMup ERP, reorder levels and safety stock are recalculated per item from real consumption and actual supplier lead times, and the system flags exactly what to reorder — or drafts the purchase order — the moment stock touches the level. Start free or see the inventory module.
Reorder Level Calculator — frequently asked questions
How do I calculate the reorder level?
Reorder level = (average daily usage × lead time) + safety stock. With 100 units/day, a 10-day lead time and 200 units of safety stock, that is (100 × 10) + 200 = 1,200 units. A common alternative is maximum daily usage × maximum lead time.
What is the difference between reorder level and safety stock?
Safety stock is the buffer against variability; the reorder level is the trigger level that includes lead-time demand plus the safety stock. Safety stock is one part of the reorder level.
How do I calculate minimum and maximum stock levels?
Minimum level = reorder level − (avg usage × avg lead time). Maximum level = reorder level + reorder quantity − (min usage × min lead time). The stock-control mode above computes both, plus the average level.
When should I reorder stock?
The instant on-hand stock falls to the reorder level. It already covers expected usage over the lead time plus a buffer, so the replenishment arrives before you run out.
Need more shop-floor tools? Browse all free calculators, or try the Safety Stock Calculator and the Inventory Turnover Calculator.
Reorder at the right moment, every time
OEMup computes reorder levels and safety stock per item from live demand and lead times — built for Indian manufacturing SMEs.
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