function calculateFBAProfit() {
var price = parseFloat(document.getElementById('fba_sellingPrice').value) || 0;
var cost = parseFloat(document.getElementById('fba_productCost').value) || 0;
var shipping = parseFloat(document.getElementById('fba_shippingToAmazon').value) || 0;
var referralPercent = parseFloat(document.getElementById('fba_referralFeePercent').value) || 0;
var fbaFee = parseFloat(document.getElementById('fba_fulfillmentFee').value) || 0;
var storage = parseFloat(document.getElementById('fba_storageFee').value) || 0;
var ppc = parseFloat(document.getElementById('fba_ppcSpend').value) || 0;
if (price 0 ? (netProfit / (cost + shipping)) * 100 : 0;
document.getElementById('res_referralFee').innerText = "$" + calculatedReferral.toFixed(2);
document.getElementById('res_totalExpenses').innerText = "$" + totalExpenses.toFixed(2);
document.getElementById('res_netProfit').innerText = "$" + netProfit.toFixed(2);
document.getElementById('res_margin').innerText = margin.toFixed(2) + "%";
document.getElementById('res_roi').innerText = roi.toFixed(2) + "%";
var resultDiv = document.getElementById('fba_results');
resultDiv.style.display = 'block';
var profitColor = netProfit > 0 ? "#1e7e34" : "#dc3545";
document.getElementById('res_netProfit').style.color = profitColor;
}
How to Calculate Amazon FBA Profits
Selling on Amazon through the Fulfillment by Amazon (FBA) program offers incredible scale, but the fee structure can be complex. To accurately calculate your unit economics, you must look beyond the simple product cost.
Key FBA Fee Components
Referral Fees: This is Amazon's commission for selling on their platform. Most categories have a 15% referral fee, though it can range from 8% to 45% depending on the niche.
Fulfillment Fees: These cover picking, packing, and shipping your product to the customer. They are determined by the weight and dimensions of your packaged unit.
Storage Fees: Amazon charges monthly storage based on the volume (cubic feet) your inventory occupies in their warehouses. Rates increase during the Q4 holiday season.
Landed Cost: This is the total cost to get your product into Amazon's warehouse, including manufacturing and freight (shipping to Amazon).
Realistic Example Calculation
Imagine you sell a Yoga Mat for $35.00. Your manufacturing cost is $8.00 and shipping to Amazon is $1.50. Amazon's 15% referral fee is $5.25, and the FBA fulfillment fee is $6.00. If you spend $3.00 per unit on PPC ads, your total cost is $23.75.
Your Net Profit would be $11.25 per unit, resulting in a 32.1% Profit Margin and a 118% ROI.
Tips for Improving FBA Margins
If your margins are slim (below 20%), consider optimizing your packaging to drop into a smaller shipping tier, renegotiating with suppliers for bulk discounts, or improving your PPC efficiency (ACOS) to lower the marketing cost per unit.