Own store, Amazon or Etsy. Product cost, shipping both ways, payment and marketplace fees, and the returns line every other calculator skips. Then the three numbers you set ad budgets with: your break even ROAS, your target ROAS, and the most you can pay for one order.
This page does the maths for one order. The Product Profit and Break Even ROAS Calculator does it for five products at once, sorted by which one earns most per order, with the what if table for each, so you know which product gets the ad budget and which one needs a price change.
Instant download. Also on Gumroad.
Get the Product Profit CalculatorPlanning the whole brand? The Ecommerce Financial Model runs orders by channel, ads, fees and fulfilment month by month for five years. $39.

Every line is something you typed or a published fee, so you can argue with any of them. The chain is the same one the paid calculator uses, so the two agree on the same order. Ad benchmarks are 2026 medians across categories; use them as a sanity check, not a target.
| Line | Rate | Where it comes from |
|---|---|---|
| Revenue | Selling price plus shipping charged to the customer. | Marketplaces charge their percentage on both, so the fee lines use the same base. |
| Payment processing | Own store 2.9% plus 30 cents. Etsy 3% plus 25 cents. Amazon 0, it sits inside the referral fee. | Shopify Payments Basic plan 2.9% plus 30 cents, Advanced 2.4% plus 30 cents; third party gateways add 0.5% to 2%. Etsy Payments 3% plus 25 cents for US sellers. |
| Marketplace fee | Amazon 15%. Etsy 6.5% plus a 20 cent listing fee per sale. Own store 0. | Amazon referral fee is 15% for most categories, 5% to 45% across all, 30 cent minimum. Etsy transaction fee 6.5% on item plus shipping. |
| Shipping you pay | $8.50 default. Amazon preset $5.50, the FBA fulfilment fee for a small standard item. | Small businesses pay $8 to $21 a parcel in 2026 before surcharges; USPS is 40% to 60% cheaper under 2 lb. Most brands run a negative shipping margin. |
| Packaging | $1.20 default. | Mailer, box, tissue and insert run $0.50 to $2.50 an order at small volumes. |
| Returns allowance | Return rate times the cost of one return, plus 15% of the product cost written off per return. | All in cost of a return $10 to $30 for parcel goods, $40 to $120 for bulky items. Rates: apparel 20% to 30%, electronics 8% to 12%, beauty 5% to 8%, general ecommerce about 15% to 20%. |
| Contribution before ads | Revenue minus product, packaging, shipping, fees and returns. | The number DTC operators plan on. Healthy stores keep 25% to 45% before ads; Amazon runs 8 to 15 points lower than a Shopify store in the same category. |
| Break even ROAS | Revenue divided by contribution, which is 1 divided by the contribution margin. | The formula every source agrees on. A 40% margin means 2.5x just to stand still. |
| Max cost per order and target ROAS | Contribution minus the profit you want to keep. Target ROAS is revenue divided by that cap. | Ad platforms optimise to a CPA cap or a target ROAS; this gives you both from the same order. |
| Typical 2026 results | Meta 2.5x to 4x, Google Shopping 3.5x to 5x, Search about 3.4x. Median CPA about $19 on Shopping, about $30 on Meta, $43 to $51 across Google campaign types. | Superscale, Hawky, Ryze and Adamigo 2026 benchmark reports. Beauty on Meta about 4.5x; electronics CPA about $49. |
Rates last reviewed September 2026. This is an estimate to plan with, not accounting advice. Fixed costs, software, salaries and your own time are not in the per order chain; the five year model carries them. Opening a shop instead of a store? Try the restaurant or coffee shop startup cost calculators.
Revenue divided by the contribution you keep per order before ads, which is the same as 1 divided by your contribution margin. A $60 order that leaves $29 after product, shipping, fees and returns has a 48% margin and a break even ROAS of 2.06x: every $1 of ads has to bring $2.06 of sales just to not lose money. The big number above does this for your order.
Typical results are 2.5x to 4x on Meta and 3.5x to 5x on Google Shopping. But good only means above your own break even plus the margin you want to keep. A 3x ROAS is excellent on a 60% margin product and a loss on a 25% margin product. Set the target from your order, not from an average.
Break even leaves nothing after ads. Target leaves the profit you chose. On a $60 order with $29 of contribution, break even is 2.06x; keeping 15% of revenue ($9) means ads can take $20 per order, so the target ROAS is 3x. Both are on the result panel.
Contribution before ads minus the profit you want. On the $60 example that is $29 minus $9, a $20 cap. Median cost per acquisition in 2026 is about $19 on Google Shopping and about $30 on Meta, so that product works on Shopping and is marginal on Meta. The max cost per order tile is the number to type into the ad platform.
Yes, and most calculators skip them. A return costs $10 to $30 all in for parcel goods, and apparel runs 20% to 30% of orders. At a 20% rate and $15 a return that is $3 per order, more than the payment fee, and it moves the break even ROAS on a $60 order from about 2.06x to about 2.3x. Set your rate above and watch the big number.
Because ROAS counts revenue, not profit. A 3x ROAS on a $60 order means $20 of ads per order. If product, shipping, fees and returns already take $35, only $25 is left and you keep $5. On a thinner product the same 3x is a loss. The what if table shows what every CPA leaves on your order.