What this calculator does
Compare up to three selling channels on unit profit, margin, ROI, break-even and target-margin price using your fee, fulfillment, advertising and return assumptions.
Selling channel economics
Marketplace Profit Comparator
Compare real unit profit across channels — fees, fulfillment, ads and returns — under your assumptions.
Planning estimate only. Fees vary by country, category, plan and date. Verify official marketplace fee schedules before decisions. Not financial, accounting or tax advice.
1. Product economics
Shared unit cost basis for every channel.
Total base cost: 40 USD
2. Channel assumptions
Fees vary by country, category, plan and date. Verify current marketplace fee schedules before making decisions. Phase A uses your inputs only — not official presets.
3. Profit comparison
Fee assumptions: User supplied
Channel A
- Profit: 21.8
- Margin: 21.8%
- Effective fee %: 33%
- Break-even price: 67.46
- Target-margin price: 96.17
Channel B
- Profit: 20.4
- Margin: 21.47%
- Effective fee %: 26.42%
- Break-even price: 66.67
- Target-margin price: 92.31
- Highest profit under current assumptions: Channel A
- Highest margin under current assumptions: Channel A
- Lowest fee burden under current assumptions: Channel B
- Profit difference (A − B): 1.4
4. Sensitivity
Advertising %
- 0% → Profit 31.8 · Margin 31.8%
- 5% → Profit 26.8 · Margin 26.8%
- 10% → Profit 21.8 · Margin 21.8%
- 15% → Profit 16.8 · Margin 16.8%
- 20% → Profit 11.8 · Margin 11.8%
Return rate %
- 0% → Profit 27 · Margin 27%
- 5% → Profit 21.8 · Margin 21.8%
- 10% → Profit 16.6 · Margin 16.6%
- 20% → Profit 6.2 · Margin 6.2%
- 30% → Profit -4.2 · Margin -4.2%
Selling price Δ%
- -10% → Profit 15.1 · Margin 16.78%
- 10% → Profit 28.5 · Margin 25.91%
5. Crossover
- At current assumptions, Channel A stays ahead of Channel B until Channel A marketplace fee ≈ 16.4%.
- Selling-price crossover for equal profit (Channel A vs Channel B): ≈ 97.91
6. Interpretation
- Channel A leaves 1.40 more profit per unit than Channel B under these assumptions, despite a higher fee stack.
- At the current assumptions, Channel A remains more profitable until its marketplace fee reaches approximately 16.4%.
- Channel A shows 21.8% margin and 21.80 profit per unit at the entered selling price.
7. Share & related tools
Key concepts
- Marketplace fee
- Platform commission usually charged as a percentage of the selling price (sometimes plus fixed fees).
- Payment processing fee
- Card or wallet processing costs — often a mix of percent and fixed amounts.
- Fulfillment fee
- Pick, pack, storage or carrier costs borne by the seller per unit.
- Advertising cost
- Sponsored placement spend as a share of selling price — treat as an explicit rate for planning.
- Return cost
- Expected loss = return rate × (selling price + processing cost). Phase A does not model marketplace-specific refunded-fee rules.
- Margin vs markup
- Margin is profit ÷ selling price. Markup is profit ÷ cost. They are not interchangeable.
- Break-even price
- The selling price where profit is zero after percentage fees and expected returns.
Informational planning tool only. Actual marketplace fees, taxes and refunds vary by country, category, plan and date. Results are not financial, accounting or tax advice. Confirm official fee schedules before decisions.
Method
All fees are user-supplied. Expected return loss is modelled explicitly. Break-even and target-margin prices use the same reverse-price algebra as International Pricing & Margin.
FAQ
Does this use official Amazon or eBay fees?
No. Phase A treats your entered rates as the source of truth. Official schedules change by country, category and plan.
Is the highest-profit channel a recommendation?
No. Labels are descriptive under your current assumptions only — not absolute marketplace recommendations.
Can I share a scenario?
Yes. Copy the ?mpc= link. It stores inputs only — no computed values or personal data.