About This Amazon FBA vs FBM Calculator
Use the Amazon FBA vs FBM calculator to compare Fulfillment by Amazon (FBA) against Fulfillment by Merchant (FBM) for the same product. The two methods have very different fee structures: FBA adds fulfillment and storage fees but can win the Buy Box and Prime badge, while FBM keeps fees lower but leaves shipping and handling to you. Comparing both side by side shows which model keeps more profit per sale for your specific product size, weight, and price.
How to Use the Calculator
- Enter the sale price for one unit.
- Enter the referral fee for your product category (usually 8-15 percent).
- Enter your per-unit product cost.
- Set the FBA fulfillment fee, monthly storage fee, FBM shipping cost, and FBM closing fee to match your product.
- Compare the FBA and FBM net profit and read which fulfillment model wins.
How the Math Works
The calculator computes referral fees from the sale price, then builds two scenarios. FBA total cost equals referral fee plus FBA fulfillment fee plus monthly storage fee. FBM total cost equals referral fee plus closing fee plus your shipping cost. Net profit for each is sale price minus product cost minus that scenario total cost. The model with the higher net profit is the winner for that product.
Calculator results are estimates, not official platform statements. Marketplace fees, processor rates, carrier charges, taxes, return costs, and discounts can change by category, region, seller account, customer location, and timing. Use the result as a planning checkpoint, then confirm important assumptions with your marketplace dashboard, accounting records, shipping software, or a qualified professional.
Interpretation Tips
- Re-run the comparison whenever product size or weight changes, because FBA fulfillment fees jump for oversized items.
- Heavy or bulky products often favor FBM because FBA fulfillment fees scale quickly with size.
- Low-priced items can be hurt by FBA fees that leave little margin.
- Storage fees mean slow-moving inventory can quietly reduce FBA profit over time.
- Use official Amazon fee schedules for final decisions because rates change by category and season.
Amazon FBA vs FBM Calculator FAQ
Which is more profitable, FBA or FBM?
It depends on product size, weight, selling price, and sales velocity. FBA adds fulfillment and storage fees but can win the Buy Box and Prime. FBM keeps fees lower but you handle shipping. Compare both scenarios for your product to see which nets more.
What fees does FBA charge?
FBA charges a referral fee (usually 8-15 percent by category) plus a per-unit fulfillment fee based on size and weight, and monthly storage fees. Some items also carry removal, disposal, or aged-inventory fees.
What fees does FBM charge?
FBM sellers pay the same referral fee plus a per-item closing fee (about 99 cents for individual sellers), and they absorb their own shipping cost. There are no FBA fulfillment or storage fees.
Should I use FBA or FBM for large products?
Large or heavy products often favor FBM because FBA fulfillment fees can be high, unless Prime eligibility drives enough extra sales to justify the cost.
Can I switch between FBA and FBM later?
Yes. Many sellers run a hybrid model and move products between the two based on size, velocity, and season. Re-run this comparison when conditions change.