FBA Profit Breakdown (Per Unit)
* FBA fees are based on approximate 2024–2025 Amazon fee schedules. Storage rates: $0.78/cu ft/mo (Jan–Sep), $2.40/cu ft/mo (Oct–Dec). Always verify current fees on Seller Central.
Amazon FBA Profit Calculator with Storage Fees
What This Calculator Does and Why It Is Useful
Most FBA sellers underestimate their true costs because they forget to include storage fees in their profit math. This free Amazon FBA profit calculator with storage fees helps you see exactly what you earn per unit after all costs — referral fees, fulfillment fees, monthly storage fees, ad spend, and your cost of goods.
Selling on Amazon FBA is one of the fastest ways to reach millions of buyers, but thin margins and hidden fees are what sink most new sellers. Having a clear picture of your per-unit economics before you launch — or before you reorder inventory — is the difference between a profitable product and an expensive mistake.
According to Amazon’s official FBA overview, fees vary based on product size, weight, and the time of year. This calculator uses Amazon’s current fee tiers so you can trust the numbers you see.
How to Use This Calculator
Step-by-Step Instructions
- Enter your product’s selling price on Amazon (the price customers pay).
- Enter your cost of goods — what you pay your supplier per unit.
- Enter your shipping cost to send inventory to Amazon FBA warehouses per unit.
- Select the Amazon referral fee percentage for your product category (15% applies to most general categories).
- Choose your product size tier from small standard to large oversize — this determines your FBA fulfillment fee.
- Enter the number of units you have in storage, the volume of each unit in cubic feet, the storage season (standard or peak), and how many months the inventory will sit.
- Add your per-unit PPC or advertising spend and any other costs.
- Click Calculate Profit to see your full cost breakdown, net profit, margin percentage, and ROI.
The Formula Explained
Breaking Down the Formula
The calculator works through three layers of costs: Amazon’s fees, your supply chain costs, and your variable selling costs. Each is deducted from the selling price to arrive at your true net profit.
Amazon’s fees include the referral fee (a percentage of the selling price) and the FBA fulfillment fee (a flat fee based on size tier). Storage fees are calculated as: monthly rate per cubic foot × cubic feet per unit × months in storage. The result is divided by the number of units to get a per-unit storage cost.
The final formula is: Net Profit = Selling Price − Referral Fee − FBA Fee − Storage Fee per Unit − COGS − Shipping − PPC − Other Costs
Example Calculation with Real Numbers
You sell a product for $29.99 in the general category (15% referral fee = $4.50). The large-standard FBA fee is $4.75. You have 100 units, each 0.5 cu ft, stored for 2 months during Jan–Sep at $0.78/cu ft/mo. Storage per unit = (0.78 × 0.5 × 100 × 2) / 100 = $0.78. COGS is $8.00, shipping to FBA is $1.50, PPC is $1.00. Total costs = $20.53. Net profit = $9.46 per unit, margin = 31.5%, ROI = 46.1%.
When Would You Use This
Real Life Use Cases
This calculator is essential at several key stages of your FBA business. Use it during product research to decide if a potential item is worth sourcing. Use it before reordering to check if your numbers still work after a fee change. Use it when running a promotion or price drop to see how much margin you have to play with.
Specific Example Scenario
A seller is considering reducing their price from $32.99 to $27.99 to win the Buy Box. By entering both prices into the calculator with all other costs the same, they can see exactly how much their per-unit profit drops — and whether the volume increase from winning the Buy Box justifies the reduced margin. Without this kind of calculation, pricing decisions are guesswork. For a deeper understanding of FBA fee structures, the Jungle Scout FBA reference guide provides useful benchmarks for sellers at all stages.
Tips for Getting Accurate Results
Use Your Actual Landed COGS, Not Just Supplier Price
Your cost of goods should include the unit price from your supplier plus any import duties, customs fees, and prep center costs. Many sellers only enter the factory price and wonder why their real profits are lower than estimated. Your true landed cost per unit is what you should enter in the COGS field for reliable results.
Do Not Ignore the October to December Storage Fee Spike
Amazon charges $0.78 per cubic foot per month for standard storage from January through September. But from October through December, the rate jumps to $2.40 per cubic foot — more than three times higher. If you plan to hold significant inventory heading into Q4, calculate your storage costs at the peak rate. Many sellers are shocked by the November and December storage charges on their first holiday season.
Factor in Your Actual Average PPC Spend, Not a Guess
PPC advertising is one of the most overlooked costs in FBA profit calculations. Newer sellers often skip this field or underestimate it. Pull your actual spend-per-unit from your advertising reports in Seller Central and use that number. If you are in the research phase and have no data yet, a conservative estimate of 10–15% of your selling price is a reasonable starting point in competitive categories.
Frequently Asked Questions
What is Amazon’s referral fee and how is it calculated?
Amazon’s referral fee is a percentage of your product’s total selling price (including shipping if charged separately). It ranges from 6% for certain electronics to 20% for jewelry and 45% for Amazon Device Accessories. The most common rate for general merchandise is 15%. Amazon deducts this automatically from each sale before depositing money into your account.
How are FBA fulfillment fees determined?
FBA fulfillment fees are based on your product’s size tier, which is determined by its weight and dimensions when packaged. Amazon classifies items as small standard, large standard, or one of several oversize tiers. Heavier and larger items have higher fees. Amazon updates these rates annually, so always verify the current fee schedule on Seller Central before making sourcing decisions.
What is the Amazon FBA monthly storage fee rate?
Amazon charges $0.78 per cubic foot per month for standard-size products stored from January through September, and $2.40 per cubic foot per month from October through December. Oversize products have slightly different rates. Long-term storage fees also apply to inventory held for more than 365 days, currently at $6.90 per cubic foot or $0.15 per unit, whichever is greater.
What is a good profit margin for Amazon FBA?
Most experienced FBA sellers target a net profit margin of at least 20–30% after all fees. Margins below 15% leave very little room for price changes, fee increases, or unexpected costs. Margins above 40% are excellent and sustainable long-term. Product category, competition, and your supply chain efficiency all affect what margin is realistically achievable.
What is ROI in the context of FBA, and what should I aim for?
In FBA, ROI (Return on Investment) measures how much profit you earn relative to the total cost invested in each unit. An ROI of 50% means for every $1 you spend on a unit (all-in), you earn $0.50 in profit. Most FBA coaches recommend targeting at least 50% ROI for private label products and 30% or more for wholesale or arbitrage sourcing to account for slow turnover periods.
Does this calculator account for Amazon’s aged inventory surcharge?
This calculator covers standard monthly storage fees. Amazon also charges an aged inventory surcharge (formerly called long-term storage fees) for items stored more than 181 days. These fees can be significant — up to $6.90 per cubic foot or $0.15 per unit per month after 365 days. If your product has slow turnover, factor in these additional charges separately or improve your inventory turnover rate.
Should I include PPC spend in my profit calculation?
Yes, absolutely. PPC advertising is a real cost of selling on Amazon and should always be included in your profit calculation. Many sellers make the mistake of looking at their Seller Central payout and thinking that is their profit — without realizing advertising costs are billed separately. Your true profit per unit only emerges when all costs, including ad spend, are accounted for.
Does the referral fee apply to the full price including shipping?
In most cases, yes. Amazon calculates the referral fee based on the total selling price, which includes any shipping charges you collect from the buyer. If you offer free shipping and roll the cost into your listing price, the referral fee applies to that full price. FBA sellers who let Amazon handle shipping do not collect a shipping charge separately, so the fee applies only to the listed product price.
Conclusion
Knowing your true per-unit profit is the foundation of a healthy Amazon FBA business. This free calculator brings together all the major costs — including the storage fees that many sellers forget — so you can make confident decisions about pricing, sourcing, and inventory levels.
Use it before every product launch, every reorder, and every pricing adjustment. The more accurate your inputs, the more useful the output. Combine this tool with regular reviews of your Seller Central reports and you will always know exactly where your money is going.