Calculating your Amazon FBA (Fulfillment by Amazon) profit is the difference between a thriving e-commerce business and a failing one. Many sellers focus on "Top Line Revenue," but your bottom line is what keeps the lights on. This tool helps you account for every hidden fee associated with the platform.
Understanding the Key Inputs
Sale Price: The final price the customer pays for your product on Amazon.com.
Product Cost (COGS): The amount you paid your manufacturer per unit, including any packaging.
Referral Fee: Amazon charges a percentage of the total sale price for "referring" the customer to you. For most categories, this is 15%.
FBA Fulfillment Fee: This covers the cost of Amazon picking, packing, and shipping your product to the customer. This depends on the size and weight of your item.
Storage Fee: Amazon charges per cubic foot for products sitting in their warehouse. This usually increases during the Q4 holiday season.
PPC Spend: Your Amazon Advertising costs divided by the number of units sold.
Example Calculation
Imagine you are selling a yoga mat for $35.00. Your manufacturing cost is $8.00. Shipping to Amazon is $1.50 per unit. The 15% referral fee is $5.25. If the FBA fulfillment fee is $6.00 and you spend $3.00 on PPC per sale, your total costs are $23.75. Your net profit would be $11.25 per unit, resulting in a 32% profit margin.
Why Monitoring Margins is Critical
Amazon fees change annually. By using this FBA calculator, you can simulate "What If" scenarios. For example, if Amazon increases fulfillment fees by $0.50, you can instantly see how that impacts your ROI. High-volume sellers use these metrics to decide which products to scale and which to liquidate.
function calculateFBAProfit() {
var salePrice = parseFloat(document.getElementById("salePrice").value) || 0;
var productCost = parseFloat(document.getElementById("productCost").value) || 0;
var shippingToAmazon = parseFloat(document.getElementById("shippingToAmazon").value) || 0;
var referralFeePct = parseFloat(document.getElementById("referralFee").value) || 0;
var fulfillmentFee = parseFloat(document.getElementById("fulfillmentFee").value) || 0;
var storageFee = parseFloat(document.getElementById("storageFee").value) || 0;
var ppcSpend = parseFloat(document.getElementById("ppcSpend").value) || 0;
var miscCosts = parseFloat(document.getElementById("miscCosts").value) || 0;
if (salePrice 0 ? (netProfit / investment) * 100 : 0;
// Display Results
document.getElementById("fba-results").style.display = "block";
document.getElementById("resRevenue").innerText = "$" + salePrice.toFixed(2);
document.getElementById("resReferral").innerText = "-$" + calculatedReferralFee.toFixed(2);
document.getElementById("resTotalCosts").innerText = "$" + totalCosts.toFixed(2);
var profitEl = document.getElementById("resNetProfit");
profitEl.innerText = "$" + netProfit.toFixed(2);
if (netProfit >= 0) {
profitEl.className = "fba-result-value profit-positive";
} else {
profitEl.className = "fba-result-value profit-negative";
}
document.getElementById("resMargin").innerText = profitMargin.toFixed(2) + "%";
document.getElementById("resROI").innerText = roi.toFixed(2) + "%";
}