Amazon FBA Calculator
Enter your selling price, product cost and fees to get net profit per unit, margin, ROI and your break-even sale price. Fees are figures you enter — Amazon's rates vary by category and change over time, so this stays accurate no matter when you use it.
Why the fees are fields, not a lookup table
Plenty of FBA calculators try to bake Amazon's fee schedule directly into the tool. The problem is that referral fee percentages differ by category (commonly 8–17%, with several categories running outside that band), FBA fulfillment fees depend on your product's size tier and weight, and Amazon updates both periodically. A hardcoded table is wrong the moment a fee changes, and wrong per-category even before that. This calculator asks for your referral fee % and FBA fulfillment fee as inputs — pull the exact current numbers for your ASIN from Seller Central's Revenue Calculator, plug them in here, and the math stays correct regardless of when Amazon last updated its rates.
What each input means
Selling price is what the customer pays. Product cost (COGS) is your landed unit cost — manufacturing plus freight to your own warehouse or 3PL, before Amazon touches it. Referral fee is Amazon's cut of the sale, entered as a percentage of selling price — this calculator defaults to 15% as a common starting point, but check your category in Seller Central since it varies. FBA fulfillment fee is the flat per-unit amount Amazon charges to pick, pack and ship the order, based on size and weight tier. Other per-unit costs covers inbound shipping to Amazon, prep and labeling, poly-bagging and similar. Advertising cost is optional — your average ad spend per unit sold, if you run Sponsored Products or similar campaigns.
A worked example
A product sells for $30, costs $8 to source (COGS), carries a 15% referral fee, a $5 FBA fulfillment fee, and $2 in other per-unit costs (inbound shipping and prep), with no ad spend. Referral fee dollars: $30 × 15% = $4.50. Net profit: $30 − $8 − $4.50 − $5 − $2 = $10.50 per unit. Net margin: $10.50 ÷ $30 = 35%. ROI on the $8 invested in inventory: $10.50 ÷ $8 = 131.25%. Break-even price — the price at which profit would hit zero given the same fees — works out to roughly $17.65.
The break-even price formula
Break-even sale price solves for the price where net profit equals zero, holding the referral fee percentage and fixed per-unit costs constant: Break-even price = (Cost + FBA fee + Other costs + Ad cost) ÷ (1 − Referral fee % ÷ 100). Because the referral fee itself is a percentage of price, you can't just add up the costs — you have to divide by the remaining share of the price after the referral cut, which is what this formula does.
| Price | COGS | Referral (15%) | FBA fee | Other | Net profit | ROI |
|---|---|---|---|---|---|---|
| $20 | $8 | $3.00 | $5 | $2 | $2.00 | 25% |
| $25 | $8 | $3.75 | $5 | $2 | $6.25 | 78.1% |
| $30 | $8 | $4.50 | $5 | $2 | $10.50 | 131.25% |
| $35 | $8 | $5.25 | $5 | $2 | $14.75 | 184.4% |
ROI versus margin — why both numbers matter
Margin tells you profit as a share of the sale price; ROI tells you profit as a share of the cash you tied up in inventory. A high-margin, low-cost product can post a huge ROI even with modest margin, because so little capital was at risk per unit — which matters a lot if you're reinvesting profit into more inventory and cash is the constraint, rather than shelf space or ad budget.
What this tool doesn't include
This calculator doesn't model long-term storage fees, returns and refund processing fees, inventory placement fees, or income tax — all of which can matter depending on your catalog and location. It also doesn't pull live fee data from Amazon; every number here is one you supply, so double-check current fees in Seller Central before finalizing pricing, and treat the output as a planning estimate rather than an exact accounting figure.
Frequently asked questions
Does this calculator know Amazon's current FBA fees?
No, and deliberately so. Amazon's referral fee percentages and FBA fulfillment fees vary by category, size tier and marketplace, and they change over time — a hardcoded fee table would go stale and mislead you. Instead you enter your own referral fee % and FBA fee, which you can find in Amazon Seller Central's Revenue Calculator or your category fee schedule, and this tool does the profit, margin, ROI and break-even math around those numbers.
Where do I find my exact referral fee and FBA fee?
In Seller Central, use the built-in Revenue Calculator (or FBA Revenue Calculator) for your exact ASIN — it shows the referral fee percentage for your category and the FBA fulfillment fee for your product's size and weight tier. Category referral fees commonly range from about 8% to 17%, with several exceptions, so don't assume a flat 15% applies to every listing.
What counts as "other per-unit costs"?
Anything not already covered by referral or FBA fees: inbound freight to Amazon's warehouse, manufacturer cost adjustments, prep and labeling, poly-bagging, long-term storage if applicable, and any packaging beyond what FBA provides. Add these up per unit and enter the total.
How is net profit calculated?
Net profit per unit = Selling price − Product cost − Referral fee − FBA fee − Other costs − Advertising cost. Referral fee is calculated as selling price × referral fee percentage. Everything else is entered as a flat per-unit dollar amount.
What does the break-even sale price mean?
It's the selling price at which net profit would be exactly zero, given your current cost, FBA fee, other costs, ad cost and referral fee percentage. If your actual price is below the break-even price, you're losing money on every unit before considering any other fees not entered here.
Is this financial advice?
No. This is a general-purpose estimate based on the numbers you enter. Always verify current fees, tax obligations and total landed costs in Amazon Seller Central and with a qualified accountant before making pricing or sourcing decisions.
Last updated: July 2026 · How we calculate
BriskToolbox provides estimates for general information only and is not financial or business advice. Fees are user-entered estimates — verify current Amazon fees in Seller Central and consult a qualified professional before making pricing or sourcing decisions.