Inventory Turnover
How many times a year does your stock turn over, in how many days does it sell out, and how much cash is tied up in the warehouse?
Safety stock
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a buffer against delays
Reorder Level and Reorder Point Calculator
The reorder level is the quantity at which you need to place a new order. When it isn't calculated correctly, one of two things happens: either you run out of goods and miss sales, or you buy more than you need and tie up your money on the shelf. This tool combines your average daily sales, the supplier's lead time and a safety margin to calculate your reorder point and the suggested order quantity.
Reorder Level Calculator
Reorder level
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place an order at this level
Order in how many days?
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Status
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The safety margin is for when the supplier is late or sales go faster than expected. If your supplier is reliable, 20% is a reasonable starting point; if they are often late, 50%.
Calculation formula
Temel ihtiyaç = Günlük ortalama satış × Tedarik süresi Güvenlik stoğu = Temel ihtiyaç × Güvenlik payı ÷ 100 Kritik stok (sipariş noktası) = Temel ihtiyaç + Güvenlik stoğu
How do I find average daily sales?
Divide the total number of units you sold in the last 30 days by 30. For seasonal products, looking at the same period last year gives a more accurate result.
If the difference between weekdays and weekends is large, take a weekly average and divide by 7; this keeps a single busy day from inflating the average.
Measure the lead time, don't guess it
There is usually a gap between your supplier saying "it'll arrive in two days" and the goods actually reaching the shelf. Record the date you placed the order and the date the goods entered the warehouse a few times, and your real average emerges.
The lead-time column in the order tracking template makes this measurement automatically.
Turn the reorder level into an automatic alert in Excel
Enter the figure you found in the "Reorder Level" column of the stock tracking template. When remaining stock falls below this number, the row automatically turns yellow, and when it hits zero, red — all you have to do is look at the list.
Frequently asked questions
Are reorder level and safety stock the same thing?
No. Safety stock is the buffer you keep against delays; the reorder level is the total level at which you need to place an order, including the safety stock. If you'd rather measure than estimate by percentage how many units the buffer should be, the safety stock calculator works it out from your highest sales and your longest lead time.
Should I calculate it separately for each product?
That's the ideal, because sales velocity and lead time vary by product. In practice, calculating it for your 20–30 best-selling products solves most of the problem.
What should I do if my supplier is often late?
Raise the safety margin (50–70%) or find a second supplier. A high safety margin means tied-up money; if delays are constant, changing suppliers is cheaper. To see how many units the delay adds to your buffer, look at the how to calculate safety stock tool — it separates the share that comes from sales fluctuation from the share that comes from supplier delay.
How do I use it for seasonal products?
Enter your pre-season daily sales forecast and keep the lead time long; update it with actual sales during the season.
Related calculators
Profit Margin Calculator
From purchase price to selling price, from selling price to margin. It shows markup on cost and margin on sales separately.
To keep this calculation in Excel
Inventory Tracking Excel
Automatically calculates remaining stock from incoming and outgoing movements, the low-stock alert, and total stock value.
Order Tracking Excel
Tracks orders by channel, status, amount and shipping tracking number; calculates delivery time in days.
Search terms: determining critical stock quantitycritical stock levelreorder pointsafety stockstock alert
Last updated: September 10, 2026