Compare Amazon FBA (Fulfilled by Amazon) and FBM (Fulfilled by Merchant) costs side-by-side including FBA fees, storage, referral fees, and self-fulfillment costs.
The FBA vs FBM Comparison Calculator helps Amazon sellers compare the total cost of using Fulfilled by Amazon (FBA) against Fulfilled by Merchant (FBM) for their products. FBA includes picking, packing, shipping, customer service, and returns handling, but comes with fulfillment fees and monthly storage fees that can significantly impact margins.
FBA fees are based on product size and weight: standard-size items cost $3.22–$6.90+ per unit, while oversize items cost $9.73+. Monthly storage is $0.87/cu ft (Jan–Sep) and $2.40/cu ft (Oct–Dec). FBM has no Amazon fulfillment fees but requires you to handle all shipping, which may cost more or less depending on your setup.
This calculator compares both options side-by-side so you can see the per-unit profit difference and decide which fulfillment method maximizes your margin for each product. Whether you are a beginner or experienced professional, this free online tool provides instant, reliable results without manual computation. By automating the calculation, you save time and reduce the risk of costly errors in your planning and decision-making process.
FBA offers convenience and Prime eligibility but can eat margins on lower-priced items. This calculator shows the exact profit difference between FBA and FBM so you can make data-driven fulfillment decisions for each SKU. Having a precise figure at your fingertips empowers better planning and more confident decisions. Manual calculations are error-prone and time-consuming; this tool delivers verified results in seconds so you can focus on strategy.
FBA Profit = Selling Price − Product Cost − Referral Fee − FBA Fee − Storage Fee FBM Profit = Selling Price − Product Cost − Referral Fee − Your Shipping − Your Fulfillment Difference = FBM Profit − FBA Profit
Result: FBA profit: $11.79/unit. FBM profit: $10.00/unit. FBA wins by $1.79
FBA: $29.99 − $8.00 − $4.50 referral − $5.40 FBA fee − $0.30 storage = $11.79/unit. FBM: $29.99 − $8.00 − $4.50 referral − $5.50 shipping − $2.00 fulfillment = $9.99/unit. FBA is $1.80 more profitable per unit, plus provides Prime eligibility for better conversion rates.
Amazon FBA fees include three components: per-unit fulfillment fees (pick, pack, ship), monthly storage fees (per cubic foot), and optional services (labeling, prep). Fulfillment fees range from $3.22 for small standard items to $9.73+ for large oversize items. Storage fees vary seasonally.
FBM is typically more profitable for: oversized items where FBA fees are $10+, slow-moving inventory that accumulates storage fees, items priced under $12–15 where FBA fees eat most of the margin, and products you can ship cheaply via USPS First Class (under 1 lb).
FBA hidden costs include inbound shipping to Amazon warehouses, removal/disposal fees for unsold inventory, and higher return rates. FBM hidden costs include your time (opportunity cost), customer service labor, return processing, and the lower conversion rate without Prime eligibility.
FBA fees depend on size and weight. Standard-size (under 20 lbs): $3.22 for small items up to $6.90+ for heavier items. Oversize items start at $9.73. Fees include pick, pack, and ship. Check Amazon's current fee schedule as rates change annually.
Monthly storage is charged per cubic foot of space your inventory occupies in Amazon's warehouse. Standard rates are $0.87/cu ft (Jan–Sep) and $2.40/cu ft (Oct–Dec). Items stored over 181 days incur a low-inventory-level fee, and over 365 days incur aged inventory surcharges.
No. FBA is typically better for: small/lightweight products, fast-selling items, Prime-eligible listings. FBM may be better for: oversized items (high FBA fees), slow-turning inventory (high storage fees), very low-priced items, and products you can ship cheaply with negotiated rates.
Yes, many sellers use a hybrid approach. Ship fast-selling standard-size items via FBA for the Prime badge, and fulfill oversized, slow-selling, or low-margin items via FBM. You can also use FBM as a backup when FBA inventory runs low.
Products with the Prime badge typically see 20–50% higher conversion rates and often win the Buy Box more frequently. This sales velocity increase may offset higher FBA fees. Factor in the revenue impact, not just the cost difference.
Amazon handles FBA returns for free (to you), but charges return processing fees for certain categories (apparel, shoes). The return rate on FBA is typically 5–15% higher than FBM because Amazon makes returns very easy for customers.