COGS Calculator

What counts as Cost of Goods Sold?

Cost of Goods Sold (COGS) includes only the direct costs tied to producing goods sold during a given period. That means opening inventory, purchases of raw materials or finished goods, direct labour (workers on the production line, not your office staff), inbound freight, and import duties. It does not include operating expenses such as rent, admin salaries, sales commissions, or marketing spend — those sit below the gross profit line.

The standard COGS formula is: Opening Inventory + Purchases + Other Direct Costs − Closing Inventory. Getting this figure right matters for two reasons. First, gross profit — and therefore gross margin — is calculated directly from COGS. Overstate COGS and you understate profit; understate it and you'll overpay tax. Second, the ATO allows COGS deductions under section 8-1 of the ITAA 1997, but only for costs genuinely incurred in producing assessable income. Misclassifying overhead as COGS can attract scrutiny during a review.

For manufacturers and importers, getting COGS right depends heavily on capturing every supplier invoice accurately — including landed costs like freight, customs duty, and currency conversion. Manual data entry introduces errors that compound over reporting periods. Businesses processing high volumes of purchase invoices are particularly exposed to COGS misstatements from coding errors or missed bills.

How to use this COGS calculator

1. Enter your opening inventory value at the start of the period (from your balance sheet or stock count).
2. Add total purchases made during the period — include raw materials, components, and freight-in.
3. Add any other direct costs such as import duties, production supplies, or direct labour if not already in purchases.
4. Enter your closing inventory value. The calculator deducts this to arrive at the cost of goods actually sold.

What is gross profit and why does COGS drive it?

Gross profit is Revenue minus COGS. Your gross margin percentage tells you how much of every sales dollar is left after covering direct production costs. A manufacturer with AU$1,000,000 in revenue and AU$650,000 in COGS has a 35% gross margin. That margin must then cover all operating expenses — rent, salaries, software, insurance — before you reach net profit. Thin gross margins leave little room for error.

Common mistake: forgetting freight and duty in COGS

Australian importers frequently record the invoice value from their overseas supplier but forget to include sea freight, customs duty, and customs broker fees in COGS. All of these are direct costs of getting goods to a saleable condition and location — they should be included in inventory cost and flow through COGS when the goods are sold. Leaving them out overstates gross margin and understates the true cost of your product.

Does COGS include GST?

No. If your business is registered for GST, record COGS exclusive of GST. The GST component is recovered via your BAS and is not a cost to your business. If you are not GST-registered, GST paid on purchases is a real cost and should be included in COGS or expensed accordingly.

How does AP automation affect COGS accuracy?

When invoices are coded manually, direct costs sometimes land in the wrong GL account — overhead coded as COGS, or freight missed entirely. Automating accounts payable means every invoice is captured, coded against the correct account, and approved before posting to your ledger, giving you a more reliable COGS figure at month-end without the reconciliation effort.