FBA Revenue Calculator — Project Your Amazon FBA Monthly Profit
Projecting monthly revenue and profit is the foundation of a sustainable Amazon FBA business, but doing it accurately requires accounting for fees, ad spend, and returns that reduce gross revenue to a much smaller net. Our free FBA revenue calculator lets you enter your selling price, cost price, monthly units sold, Amazon fees percentage, ad spend percentage, and returns percentage to instantly compute your monthly revenue, gross profit, net profit, ROI, and the break-even number of units. Whether you are validating a product idea, building a business plan, or stress-testing whether a price change keeps you profitable, this tool gives you a clear monthly projection in seconds. Enter your numbers above to project your FBA revenue and profit.
Revenue, Gross Profit, and Net Profit — The Full Stack
Monthly revenue is simply selling price multiplied by units sold, but it is the top of a stack of deductions. Subtracting the cost of the goods sold (cost price times units) gives gross profit, the money left to cover fees, advertising, and returns. Subtracting Amazon fees (referral plus FBA fulfillment plus storage, expressed as a percentage of revenue), ad spend (PPC as a percentage of revenue), and returns (the revenue lost to refunded sales, as a percentage) gives net profit, the money you actually keep. The calculator performs each step so you can see how a healthy revenue figure shrinks through each layer to a final net. Understanding this stack is essential because two products with identical revenue can produce very different net profit depending on their cost structure, fee profile, and return rate.
ROI and Break-Even Units
Net profit in dollars tells you how much you earn, but ROI tells you how efficiently your capital works. ROI is net profit divided by total cost (cost price times units), expressed as a percentage. A high ROI means your inventory investment returns multiples of itself each month, freeing capital to reinvest; a low ROI means capital is tied up for modest returns and the business scales slowly. Most successful FBA sellers target monthly ROI above 50 percent, because the risks of inventory obsolescence, account suspension, and fee changes mean thinner margins rarely justify the capital and effort. The break-even units figure the calculator produces shows how many units you must sell each month just to cover costs and fees, a useful floor: if your realistic monthly volume sits close to break-even, the product is too risky, while volume well above break-even gives you a safety margin against demand fluctuations.
Modeling Realistic Fee, Ad, and Return Rates
The accuracy of the projection depends on the percentages you enter. Amazon fees typically run 30 to 40 percent of revenue for FBA sellers, combining the referral fee (around 15 percent) and the fulfillment plus storage fees (often 15 to 25 percent depending on size and weight). Advertising spend varies wildly by category and competition, but 10 to 15 percent of revenue is common for competitive products, and new products often require more initially to gain ranking. Returns range from a few percent for low-risk goods to 15 percent or more for apparel and electronics. Be honest with these inputs: modeling 5 percent fees and 5 percent ads paints an unrealistically rosy picture that collapses in reality. Use conservative figures, and if the product still looks profitable, it is far more likely to survive the friction of real-world FBA selling.
Using the Calculator to Make Decisions
Use the projection to compare products before you invest in inventory: the one with the higher net profit and ROI at realistic fee and ad rates is the better capital allocation, even if its gross revenue is lower. Use it to test pricing changes: enter a higher selling price and watch how net profit and break-even units move, then weigh the higher margin against the likely lower volume. Use it to set ad spend budgets: the ad percentage you enter corresponds to a dollar amount of monthly PPC spend, which you can compare against the net profit to confirm advertising is profitable rather than merely driving revenue. Re-run the numbers whenever a key input changes — a supplier price increase, a fee revision, a competitor entering the market — since each shift can quietly turn a profitable product into a marginal one if you do not recompute.
Frequently Asked Questions
What percentage should I use for Amazon fees? A combined 30 to 40 percent of revenue is typical for FBA, covering referral, fulfillment, and storage. Use the FBA Calculator on this site for a per-unit fee breakdown, then enter the equivalent percentage here.
How much should I budget for ads? 10 to 15 percent of revenue is common for competitive products; new products often need more initially. The ad percentage here converts directly to a monthly PPC budget you can sanity-check against net profit.
What is a good break-even margin? Aim for realistic monthly volume at least 1.5 to 2 times the break-even units, so demand dips or fee changes do not push the product into loss.
Bookmark this FBA revenue calculator to project monthly profit and ROI on every product before you commit capital.
