Calculation formulas and information policy
We publish the formulas, included costs, exclusions, and official sources used by the calculators.
Official information last checked:
Core formulas
- Profit
- selling price − selling fee − item cost − shipping − packaging
- Profit margin
- profit ÷ selling price × 100
- Sourcing ROI
- profit ÷ item cost × 100
- Break-even price
- (item cost + shipping + packaging) ÷ (1 − fee rate)
- Monthly profit
- profit per sale × monthly units sold