Methodology
Every SellerCalc tool uses the same shape: take your inputs, apply the marketplace's published fee structure, and output net profit plus a health score. Here are the formulas in plain English.
Universal profit formula
Net profit per sale = Selling price − Product cost − Marketplace fees − Shipping − Advertising − Returns loss.
Profit margin = Net profit ÷ Selling price × 100.
Health score: below 10% = poor, 10–20% = acceptable, 20–30% = good, above 30% = excellent.
Break-even formula
Break-even units = Fixed monthly costs ÷ (Selling price − Variable cost per unit).
Break-even revenue = Break-even units × Selling price.
ROAS formulas
ROAS = Revenue from ads ÷ Ad spend.
True ROAS = (Revenue from ads − COGS) ÷ Ad spend.
Break-even ROAS = 1 ÷ Gross margin (as a decimal).
Pricing formula
Recommended price = (Cost + Shipping) ÷ (1 − Desired margin − Platform fee), where all percentages are decimals.
Per-platform fee assumptions
- Shopify: Plan transaction fees (2% Basic, 1% Shopify, 0.5% Advanced) applied only on non-Shopify-Payments gateways. Gateway fees: Shopify Payments / Stripe 2.9% + $0.30, PayPal 3.49% + $0.49.
- Etsy: $0.20 listing fee, 6.5% transaction fee on (price + shipping), 3% + $0.25 payment processing (US), 15% offsite ads when applicable.
- Daraz Pakistan: Category commission 5–12%, COD service fee ~3%, plus shipping and packaging deductions.
- TikTok Shop: Platform commission ~8% + your set creator affiliate %.
All calculators
- Shopify · Shopify Profit Calculator
- Shopify · Shopify Break-Even Calculator
- Shopify · Shopify Goal Calculator
- Etsy · Etsy Fee Calculator
- Etsy · Etsy Profit Calculator
- Daraz · Daraz Profit Calculator (Pakistan)
- Daraz · Daraz Fee Calculator (Pakistan)
- TikTok Shop · TikTok Shop Profit Calculator
- TikTok Shop · TikTok Shop Fee Calculator
- Advertising · ROAS Calculator
- Advertising · ROI Calculator
- Advertising · Break-Even ROAS Calculator
- Pricing & Goals · Product Pricing Calculator
- Pricing & Goals · Break-Even Calculator
- Pricing & Goals · Conversion Rate Calculator
- Pricing & Goals · Sales Goal Calculator