FBA Profit & Break-Even Calculator by ReadyStack

Amazon's referral fee is 15% in most categories with a $0.30 per-item minimum (Amazon Seller Central published US fee schedule): quote a supplier without it and every unit in that purchase order ships at a loss.


Click Add to Firefox on this page. Nothing to unzip, no developer mode - the free version runs right away.

• Filled-in unit economics on open — The popup opens on a worked example (a $24.99 unit at $6.50 landed from the factory), so you see a finished profit, margin and ROI line in three seconds instead of an empty form. Replace the numbers with your own quote and every line recalculates as you type.
• Break-even price and max supplier cost — The two numbers you take into a supplier call: the sale price below which this unit loses money, and the highest per-unit cost you can accept and still break even at your current price. Send the max supplier cost as your target price instead of guessing a discount.
• Whole-order profit and cash out — Multiplies the per-unit result by your order quantity: what the whole purchase order earns, and how much cash leaves your account for goods, freight and prep before Amazon pays you anything.
• Saved supplier scenarios, compared side by side — Name and store each quote (Supplier A 500 pcs, Supplier B 1000 pcs) in the browser's local storage and open them side by side. Nothing is uploaded; the numbers stay in your profile and the tool keeps working with no connection.
• Every fee field says where the real number comes from — The fulfilment fee, referral percentage and storage fields are yours to fill from your ASIN's fee preview in Seller Central and Amazon's published fee schedule — this tool never guesses a fee for you, so the answer is as current as the number you paste in. The assumption behind the returns line is printed on screen: a returned unit is treated as unsellable, so you lose its fulfilment fee and its landed cost.

| You type | |
|---|---|
| Your list price on Amazon | default 24.99 |
| Supplier price per unit (quote) | default 6.5 |
| Freight to Amazon per unit | default 1.2 |
| Prep, labelling and polybag per unit | default 0.55 |
| Referral fee for your category (from Amazon's fee schedule) | default 15 |
| FBA fulfilment fee per unit (from your ASIN's fee preview) | default 5.4 |
| Storage cost per unit for the whole time it sits | default 0.24 |
| Advertising spend per unit sold | default 2 |
| Your return rate for this product | default 3 |
| Units in this purchase order | default 500 |

| It answers | |
|---|---|
| Landed cost per unit (goods + freight + prep) | USD |
| Amazon fees per unit (referral + fulfilment + storage) | USD |
| Returns cost spread over every unit sold | USD |
| Net profit per unit | USD |
| Net margin | % |
| Return on the cash you spend on goods | % |
| Break-even list price | USD |
| Highest supplier price you can still accept | USD |
| Net profit on the whole purchase order | USD |
| Cash out before Amazon pays you | USD |

Permissions requested: storage, clipboardWrite


Free: the calculation in the popup, no key, no limit. Full version ($29): download the result as .csv - one licence key per person or team seat. Get it: https://getreadystack.com/api/buy/cl/polar_cl_mjBFoZycL19l5RS4Uqev8RrpbIiqri1BUJ1Lp3RZLqt


When you use the tool, the extension sends one anonymous count a day (the tool’s name only — no inputs, no personal data). Turn it off on the first page after install. Firefox asks first and sends nothing unless you allow it. A licence key is checked with the payment provider (Polar) only when you enter one.