Valuation · WAC · Stock cost
A fair price,
recalculated on every entry
When you enter products with a purchase price, GSE-Web doesn't just store it. It calculates the WAC — the weighted average cost of what you actually hold in stock. Automatically, on every receipt. No hidden fees.
Entries
WAC recalculated
Issues
WAC unchanged
Method
Accounting standard
GSE-Web — Product stock sheet
Ref. BOUL-500 — T55 flour (25 kg bag)
Same product, 3 distinct stock lines: the location, warehouse or best-before date differ.
Auto
recalculated on every entry
0
manual entry of the average cost
3 dec.
of precision on the WAC
Standard
recognised accounting method
Why the same product has several stock lines
GSE-Web does not mix stock that has nothing in common. A “stock line” only groups together what is genuinely identical.
For a single product, GSE-Web creates a distinct stock line as soon as one of these characteristics changes:
The warehouse
Stock of the same product is kept separate per warehouse / site. With no warehouse specified, it joins the general stock.
The location
Aisle, shelf, level: each physical location has its own line. An empty (unspecified) location is treated as one and the same location.
The best-before date
Two batches of the same product with different best-before dates stay separate — essential for traceability and FIFO.
The batch number
If per-batch quality control is enabled on the product, the internal batch number becomes an additional separation criterion.
What does NOT create a new line
The packaging (unit, case, pallet) and the purchase price do not create a separate line. They are updated on the existing line and always reflect your latest receipt. Two identical entries (same warehouse, location, best-before, batch) merge: the quantities add up, and that is where the WAC comes in.
What is the WAC?
WAC = Weighted Average Cost. It is the average cost of one unit of product, weighted by the quantities actually held in stock. When you receive the same product at different purchase prices, GSE-Web doesn't keep only the last price or a plain average: it calculates an average that accounts for how much you bought at each price.
What it is for
- Valuing your stock: the value of a line = quantity × WAC.
- Knowing your real margin: you compare your selling price with an accurate purchase cost.
- Smoothing supplier price swings instead of being stuck with the price of the latest delivery note.
How is the WAC calculated?
One single formula, applied automatically on every stock entry.
Formula applied on every receipt
WAC = ( current WAC × quantity in stock + entered quantity × entry purchase price ) ÷ ( quantity in stock + entered quantity )
First entry of a product (empty stock): the WAC is simply the purchase price of that entry.
Worked example
Let's follow a product bought twice, then partly issued.
Entry 1 — 100 units at €2.00
Stock was empty. The WAC becomes the purchase price.
WAC = €2.000Entry 2 — 50 units at €2.60
GSE-Web weights the old stock against the new receipt:
(100 × 2.00 + 50 × 2.60) ÷ (100 + 50) = 330 ÷ 150
WAC = €2.200Issue — 30 units
An issue never changes the WAC. It stays at €2.200. Only 120 units remain.
Stock value = 120 × €2.200 = €264.00The WAC is rounded to 3 decimals. The displayed value of each line is always quantity × WAC.
Entries, issues: what moves and what stays put
On entry
The WAC is recalculated with the formula above. This is the only time it changes: receiving stock at a new price shifts the average.
On issue
The WAC does not move. Issuing stock changes neither the average cost nor the price of the remaining units — it only reduces the quantity.
What about FIFO?
For perishable products, issues follow FIFO: GSE-Web draws first from the batch with the nearest best-before date (first in, first out), to limit waste. FIFO governs the order in which batches are drawn; it does not touch the WAC calculation.
No hidden fees
GSE-Web's WAC is not a black box.
Standard accounting method
The Weighted Average Cost is one of the stock valuation methods recognised by accounting standards. Nothing invented: the very method your accountant expects.
No margin injected
GSE-Web adds no coefficient or hidden margin into the WAC. It reflects only your real purchase prices and real quantities.
Formula visible in the app
The WAC is shown on the product sheet, and the displayed stock value is always quantity × WAC. You can redo the calculation by hand at any time.
The true value of your stock,
calculated for you.
Automatic WAC, transparent formula, accurate valuation. GSE-Web does the maths on every receipt — you stay in control.
Frequently asked questions
What is the WAC in GSE-Web?
The WAC (Weighted Average Cost) is the average cost of one unit in stock, weighted by the quantities. GSE-Web recalculates it automatically on every product entry, from your real purchase prices.
Does the WAC change when I issue stock?
No. The WAC is only recalculated on entries. An issue reduces the quantity but leaves the average cost unchanged. For perishable products, the issue order follows FIFO (nearest best-before first).
Why does the same product appear on several stock lines?
Because the warehouse, location, best-before date or batch number (if quality control is enabled) differ. Packaging and price, however, do not create a distinct line: they reflect the latest receipt.