Separate Czech VAT from the CZK selling price
At 21% standard VAT, CZK 799.00 contains CZK 138.67 of output VAT and CZK 660.33 of revenue excluding VAT. Divide by 1.21 rather than subtracting the VAT percentage from gross sales.
Revenue excluding VAT = CZK 799.00 / 1.21 = CZK 660.33; output VAT = CZK 799.00 − CZK 660.33 = CZK 138.67Keep the CZK 799.00 order as a reproducible baseline
Assume a 9% platform fee and a 10% creator rate on half of comparable orders, equivalent to a 5% blended creator cost in this equal-value example. The product costs CZK 280.00, fulfilment CZK 75.00, packaging CZK 12.00 and advertising CZK 80.00 per order. These are invented inputs for checking the arithmetic, not Czechia market averages.
The example has no buyer-paid shipping, coupons or refunds. Costs use a consistent basis excluding recoverable input VAT where applicable; displayed amounts are rounded after calculation.
Subtract the direct costs from CZK 660.33 of revenue excluding VAT to get CZK 101.47 of contribution. A 10% contribution target on gross sales would reserve CZK 79.90. Compare that target with the actual result before committing to a discount, creator offer or higher ad budget.
| Line | Amount | Basis |
|---|---|---|
| Revenue excluding VAT | CZK 660.33 | CZK 799.00 / 1.21 |
| Platform commission | CZK 71.91 | 9% of gross item amount |
| Blended creator cost | CZK 39.95 | 10% rate × 50% attributed share |
| Product cost | CZK 280.00 | Illustrative landed cost |
| Fulfilment + packaging | CZK 87.00 | Illustrative direct expense |
| Advertising | CZK 80.00 | Illustrative allocated spend |
| Contribution | CZK 101.47 | Before unallocated overhead and business taxes |
Measure the rounded promotional price
If gross price falls from CZK 799 to CZK 749 while the other inputs stay fixed, contribution falls from CZK 101.47 to CZK 67.15. Check the rounded offer against the price floor and the actual local cost conversion rather than changing price automatically with every exchange-rate movement. An eligible account may use 2% for 90 days, but the regular-rate result should remain visible.
The price test holds advertising at CZK 80 per order. To reproduce it, enter CZK 749 as the price and set Ad spend / gross product sales to 80 ÷ 749 × 100 (about 10.6809%). Otherwise the calculator will reduce ad spend with the price.