How to Calculate Profit Margin (Without Guessing)
Most ecommerce sellers think they know their margin, but they’re usually missing at least one of these:
- Payment processing fees (percentage + fixed) — including Shopify fees
- Shipping (or shipping subsidies)
- Advertising cost per purchase (CPA)
- Taxes (VAT/GST when prices are tax-inclusive)
Profit Margin Calculation Formulas
Net Profit per sale
Net Profit = Revenue (net of tax) − Product Cost − Shipping − Ad Spend − Platform Fees
Profit Margin %
Profit Margin % = (Net Profit ÷ Selling Price) × 100
Markup %
Markup % = ((Selling Price − Product Cost) ÷ Product Cost) × 100
How Do You Calculate Profit Margin Percentage?
1. Subtract every real cost from selling price 2. Divide the remainder by selling price 3. Multiply by 100
That is how to calculate a profit margin operators actually use — the same method behind our margin calculator tools.
A Real Example
Sell at $49.99:
- Product cost: $15.00
- Shipping: $4.50
- Platform fee: 2.9% + $0.30
- Ads per sale (CPA): $8.00
Run these in the calculators to see net profit, profit margin calculation, and daily/monthly/yearly projections.
👉 Shopify Profit Calculator USA
Tip: If you can’t confidently explain where every dollar goes, you’re not ready to scale spend.