Free calculator
How long what you hold will actually last, in days and weeks, valued at landed cost, and measured against the one thing that decides whether it is enough: your supplier's lead time.
Days of cover
33,2days
Velocity
12,67
units a day
Weeks of cover
4,7
at that pace
Stock value
€8.043,00
at landed cost
What the cover is worth, and what it has to survive
Cover is only comfortable relative to how long a replacement takes to arrive.
↑ ↓ to nudge, Shift for ten. Commas or dots both work.
Cover is a ratio, not a quantity: 400 units is generous on a slow product and a fortnight of panic on a fast one. The only comparison that matters is cover against lead time, which is what the reorder point calculator turns into a decision.
The stock runs out 11,8 days before a purchase order placed today could arrive, which is about 150 units of demand with nothing on the shelf.
An estimate from flat rates. In nouz every order is priced from the costs of its own day.
A stock coverage calculator divides the units you hold by how fast they sell to give days and weeks of cover. It values that stock at landed cost and compares the cover with your supplier's lead time, which is the comparison that decides whether an order is already late.
The formula
Four hundred units is a comfortable position on one product and a fortnight of panic on another. Converting stock into days of cover makes every SKU comparable, and makes the only question that matters answerable: will this last long enough for a replacement to arrive?
That is why the lead time is an input rather than an afterthought. Cover shorter than the lead time means an order placed today lands after the shelf is empty, so the stockout is already scheduled and the only remaining decision is how much demand falls into the gap.
Stock is valued at landed cost here, never at retail, because inventory is money already spent rather than revenue hoped for. A store with generous cover everywhere is not well run; it is financing its warehouse.
Where it goes wrong
Cover is a simple ratio with four quietly unreliable inputs.
Seven days after a campaign flatters nothing and terrifies everyone; a year of history hides a product that has doubled since spring. Thirty to ninety days of recent, ordinary trading is usually the honest middle, and seasonal products need the same season last year rather than last month.
The agreed lead time and the observed one are different numbers, and only one of them has ever failed you. Use what the last few purchase orders actually took, including customs and putaway, because the shelf does not care what the contract said.
Damaged units, customer returns awaiting inspection and stock reserved for a wholesale order are all in the warehouse and none of them can be sold to the next customer. Counting them as cover is how a well-stocked product goes out of stock.
A product with plenty of cover in three sizes and none in the two that actually sell is out of stock in every way that matters to a customer. Cover belongs at the level people buy at, which is the variant, not the product.
Worked example
The calculator’s defaults: 420 units on hand, 380 sold in the last 30 days, a landed cost of €19,15 and a supplier who takes 45 days from order to saleable stock.
That is 12,67 units a day, so the stock lasts 33,2 days and the warehouse is holding €8.043 of cost.
An order placed today arrives 11,8 days after the shelf empties, which at this velocity is 150 units of demand with nothing to sell. The reorder was due almost a fortnight ago, and no expediting changes that arithmetic now.
This is why cover is monitored rather than checked: the moment to act was when cover crossed 45 days, not when it looked low. The reorder point calculator turns that into a number to watch.
In the app
A calculator works from flat rates you type once. nouz prices every single order from the cost rules that were in force on that order's own date, and rebuilds the same statement every night from your own orders and your own ad spend.
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The long version
Want the long version rather than the arithmetic?
Bestseller list≠ profit listfour forces reorder it11 min readWhich products actually make money? Rebuild the bestseller listYour bestseller list is a revenue ranking. Rebuilt as a profit ranking, it reorders: discounts, returns, parcels and fees decide which products actually earn.Which products actually make moneynouz computes velocity, cover and stock value per variant from your own orders and your own costs, so the products drifting toward a stockout surface before they get there.