Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Net profit per unit
$13.14
Margin
43.8%
Referral fee per unit
$4.50
Breakeven sale price
$14.53
Projected monthly profit
$3,942
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How to use this
- 1Enter sale price ($).
- 2Enter referral fee rate (%).
- 3Enter fba fulfillment fee ($).
- 4Enter storage cost per unit ($).
- 5Enter cost of goods (incl. inbound freight) ($).
- 6Enter units sold per month.
- 7Read your net profit per unit on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Amazon takes a referral fee (usually 8-17% of sale price depending on category) plus a fulfillment fee driven by size tier and weight. Sellers who only look at their cost of goods routinely misprice listings and discover the real margin only after a month of sales data. This tool combines the referral cut, a flat FBA fulfillment fee you look up from Amazon's fee tables for your size tier, monthly storage cost allocated per unit, and your landed product cost to show true per-unit and per-order profit before ad spend. Enter your sale price, category referral rate, per-unit FBA fee, monthly storage cost divided across expected units sold, and cost of goods including inbound freight. The output shows net profit per unit, margin percentage, and breakeven sale price so you can tell instantly whether a listing is worth running or needs a price increase before you commit inventory dollars to it.
Worked example
Using the values the calculator loads with:
Inputs
- Sale price: 29.99 $
- Referral fee rate: 15 %
- FBA fulfillment fee: 5.5 $
- Storage cost per unit: 0.35 $
- Cost of goods (incl. inbound freight): 6.5 $
- Units sold per month: 300
Results
- Net profit per unit: $13.14
- Margin: 43.8%
- Referral fee per unit: $4.50
- Breakeven sale price: $14.53
- Projected monthly profit: $3,942
What each field means
Inputs
- Sale price ($)
- The sale price used in the calculation, measured in $. Starts at 29.99 $ so you have a working example on load.
- Referral fee rate (%)
- The referral fee rate used in the calculation, measured in %. Starts at 15 % so you have a working example on load. Accepted range: 0–45 %.
- FBA fulfillment fee ($)
- The fba fulfillment fee used in the calculation, measured in $. Starts at 5.5 $ so you have a working example on load.
- Storage cost per unit ($)
- The storage cost per unit used in the calculation, measured in $. Starts at 0.35 $ so you have a working example on load.
- Cost of goods (incl. inbound freight) ($)
- The cost of goods (incl. inbound freight) used in the calculation, measured in $. Starts at 6.5 $ so you have a working example on load.
- Units sold per month
- The units sold per month used in the calculation. Starts at 300 so you have a working example on load.
Results
- Net profit per unit
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Margin
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Referral fee per unit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Breakeven sale price
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected monthly profit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Where do I find my exact FBA fulfillment fee?
Amazon publishes size-tier fee tables (updated at least yearly) in Seller Central under Fulfillment by Amazon Fee Schedule. Fees depend on unit weight and dimensions after accounting for dimensional weight on oversized items, so measure your actual packaged product rather than guessing a tier.
Does this include advertising cost?
No. This calculates contribution margin before PPC. Subtract your ACoS-driven ad spend per unit separately, since ad cost varies by campaign and isn't a fixed per-unit fee like referral or fulfillment charges are.
Why is my referral fee rate different from the category default?
Amazon applies minimum referral fees (often $0.30-$2.00) on low-priced items regardless of the percentage, and some categories like media or jewelry have different tiered rates above certain price thresholds. Check the exact category page in Seller Central.
What counts as a good FBA margin?
Most experienced private-label sellers target 20-30% net margin after all Amazon fees but before ads, since PPC typically consumes another 5-15 points. Anything under 15% pre-ad margin leaves little room to compete on price or survive a fee increase.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
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Contribution Margin Per SKU Calculator
See which products actually make money after every variable cost.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Amazon FBA Fee & Profit Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/amazon-fba-fee-profit
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/amazon-fba-fee-profit" target="_blank" rel="noopener">Amazon FBA Fee & Profit Calculator — RevenueLab</a> (2026).</p>
Source: [Amazon FBA Fee & Profit Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/amazon-fba-fee-profit) (2026).