E-commerce Profit Calculator — Margins, Returns & Break-even ROAS

Profit Calculator

Model real unit economics before you buy inventory. Returns are treated as lost revenue plus lost unit cost, which is where most margin disappears.

Pre-fill from a product (uses estimated bands)

Your inputs

Selling pricePer unit, excluding taxProduct costSupplier price per unitShipping costInbound + outbound per unitPackaging costBox, insert, labelsPayment fee %Typically 2–3%Marketplace fee %0 for your own storeAd cost per orderYour blended CPAReturn rate %Use the product return-risk bandUnits soldUsed for the totals below

Per unit

Profitable

Net profit / unit

$9.59

Net margin

25.9%

Gross profit / unit

$19.72

Break-even ROAS

2.10

Minimum return on ad spend

Cost breakdown / unit

Effective revenue (after returns): $37.05
Payment fee: $1.13
Marketplace fee: $0.00
Loss on returned units: $0.83
Ad cost: $9.00
Total cost: $27.46

Totals for 100 units

Revenue

$3705.00

Net profit

$959.40

Pre-filled figures come from estimated price and cost bands, not supplier quotes. Replace them with your real numbers — duties, VAT/GST and warehousing are not included.