Profit Margin Calculator

What is a profit margin?

A profit margin is the percentage of revenue that remains once your costs are paid. It answers the only question that really matters in e-commerce: how much do you actually keep from every sale? Revenue is vanity — a store can generate $100,000 a month and still lose money if its margins are broken.

Two levels matter for an online store:

• Gross margin — what's left after the direct cost of the product (COGS: purchase price, manufacturing, packaging).
• Net margin — what's left after all costs: product, shipping, payment fees, advertising, apps, returns and overheads.

Most stores only track gross margin and get a nasty surprise at the end of the month. The gap between the two is where e-commerce businesses quietly die: a product with a comfortable 70% gross margin can easily end up with a 5% net margin once ads and shipping are paid.

Profit margin formula: how is it calculated?

The two formulas used by the calculator are:

• Gross margin (%) = (Revenue − COGS) ÷ Revenue × 100
• Net margin (%) = (Revenue − Total costs) ÷ Revenue × 100

where total costs include the product cost plus every additional expense tied to the sale: shipping, transaction fees, advertising spend, and operating expenses.

Margin calculation examples in e-commerce

Example 1 — A healthy product

• Selling price: $60
• Product cost: $15
• Shipping + fees: $8
• Ad cost per sale: $18

Result: $19 net profit per sale, a 31.7% net margin. This product can absorb rising ad costs and still stay profitable.

Example 2 — A trap product

• Selling price: $25
• Product cost: $8
• Shipping + fees: $6
• Ad cost per sale: $12

Result: a $1 loss on every sale. A 68% gross margin, and the store still loses money — this is exactly why net margin is the number to watch.

How to use the profit margin calculator?

1. Choose your currency ($, € or £).
2. Selling price — the price your customer pays.
3. Product cost — purchase or production cost per unit.
4. Additional costs — shipping, payment processing, advertising per sale, and any other expense.

The calculator instantly returns your profit per sale, your gross margin and your net margin, so you can see in seconds whether a product deserves your ad budget.

Tip: run the numbers before testing a product. A product that needs everything to go perfectly to break even is not a product — it's a gamble.

What is a good profit margin in e-commerce?

Benchmarks vary by niche, but as a rule of thumb:

• Net margin < 5%: fragile — one ad-cost spike wipes you out.
• 5% to 10%: average — viable at volume, but watch every cost line.
• 10% to 20%: good — the range most healthy DTC stores live in.
• > 20%: excellent — you have real room to scale ad spend.

For paid acquisition, most media buyers look for at least a 3× markup between product cost and selling price, so the margin can absorb the real cost of ads.

How to improve your profit margin?

1. Negotiate your COGS — even $1 saved per unit goes straight to net profit.
2. Raise average order value — bundles, upsells and free-shipping thresholds spread fixed costs over a bigger basket.
3. Cut shipping waste — lighter packaging and the right carrier tier often save several points of margin.
4. Kill unprofitable ads — track your break-even ROAS and cut campaigns below it.
5. Sell products with proven demand — that's what Trendtrack is for: finding winning products with healthy economics before you spend a dollar.

Go further with Trendtrack

Margin tells you whether each sale makes money. Trendtrack tells you which products are worth selling in the first place: spot winning products, analyze competitor stores and see which ads are scaling — updated every 24 hours.

Discover our other free tools too:

• Ecom Profit Calculator
• ROAS Break Even Calculator
• ROI calculator
• Customer Lifetime Value (CLV) calculator