COS Calculator (Cost of Sales)
COS is a key metric for e-commerce. It shows what percentage of revenue goes to ads. Lower COS = higher efficiency.
CZ/SK kontext & benchmarky
How to Optimize
- › Increase AOV: cross-sell, upsell, bundles › same costs, higher revenue › lower COS
- › Lifetime value: if you have high LTV, you can afford higher COS on the first purchase
- › Product mix: products with higher margins allow for more aggressive COS
- › Retention marketing: email, SMS remarketing have lower COS than cold traffic
Frequently Asked Questions (FAQ)
Should I include agency fees and production in COS?
From a business owner's perspective (Business COS), definitely YES. Ads cost you fees too, not just credit. However, for optimization in Ads manager (Media COS), look only at direct spend to avoid skewing data.
What is the difference between PNO and COS?
They are the same. PNO (Podíl Nákladů na Obratu) is a common CZ/SK term. COS (Cost of Sales) or ACOS (Amazon Cost of Sales) are English equivalents. The formula is identical.
Why COS sometimes lies (COS vs POAS)?
COS looks at revenue, not profit. If you have product A with 5% margin and product B with 50% margin, the same 10% COS means a loss for product A, but super profit for product B. That's why advanced e-shoppers track POAS (Profit on Ad Spend).
Why does it matter?
COS is the "holy grail" of e-commerce profitability. Unlike ROAS (which is an abstract ratio, e.g.
5:1), COS tells you exactly what % of every order you "handed over" to Google or Facebook.
Keeping COS under control is critical for cash flow. If you have a 30% margin and your COS is 25%, only
5% remains to
cover
warehouse, rent, and people. That is dangerously low. The COS calculator helps you set
limits you must not cross in campaigns.