Amazon FBA vs FBM calculator (US)
Let Amazon fulfill it, or ship it yourself? The answer is different for every product. Enter your price, cost and the fulfillment costs on each side to see net profit per unit for FBA and FBM side by side — and which one actually keeps you more. Nothing is hard-coded, and nothing leaves your browser.
FBA nets $0.30 more per unit at these numbers.
Net profit per unit
FBA
$11.79
39.3% margin
Higher profit
FBM
$11.49
38.3% margin
FBA nets $0.30 more per unit at these numbers.
Profit isn't the whole story: FBA usually means the Prime badge, Amazon customer service and faster shipping, which can lift conversion — weigh that against the per-unit difference.
“Email me my result” opens your own email app with the numbers filled in — we don't see or store them.
How it's worked out
- Referral fee = selling price × referral % — charged on both FBA and FBM.
- FBA profit = price − referral − FBA fee − product cost − inbound shipping − storage.
- FBM profit = price − referral − product cost − ship-to-customer − packaging.
- The difference is FBA profit − FBM profit; the higher of the two is highlighted.
These are estimates from the figures you enter. Beyond the per-unit number, FBA usually brings the Prime badge, Amazon customer service and faster shipping — which can lift conversion enough to outweigh a small FBM cost advantage. Storage and returns also vary by season, so use your own recent numbers.
FBA vs FBM questions Amazon US sellers ask
What's the difference between FBA and FBM?
FBA (Fulfillment by Amazon) means you send inventory to Amazon and it picks, packs, ships and handles customer service — for a per-unit fulfillment fee plus storage. FBM (Fulfillment by Merchant) means you store and ship every order yourself. The referral fee is charged either way; the calculator compares only the fulfillment costs that differ.
Which is more profitable, FBA or FBM?
It depends on the item. FBA usually wins for small, light, fast-moving products where Amazon's fulfillment is cheaper than your own shipping. FBM often wins for large, heavy or slow-moving items where FBA fees and storage are steep and your own freight is cheaper. Enter your real numbers and this calculator shows the per-unit difference.
Does the referral fee change between FBA and FBM?
No. The referral fee is a percentage of the sale price charged on every Amazon order regardless of who fulfills it, so it is the same on both sides. What differs is fulfillment: FBA adds Amazon's fulfillment fee, inbound shipping and storage; FBM adds your ship-to-customer and packaging costs.
Should I choose purely on profit per unit?
No — treat the per-unit number as one input. FBA usually earns the Prime badge, Amazon-handled customer service and faster delivery, which can raise your conversion rate and sales volume. If FBM is only slightly cheaper per unit, the FBA sales lift may still make it the better choice.
Does this send my numbers anywhere?
No. The calculation runs entirely in your browser — nothing you type is sent to us or any server. Only the early-access email leaves your browser, if you choose to join the list.
Related free tools
- FBA profit & break-even calculator — net profit, margin, ROI and break-even ACOS for one fulfillment path.
- PPC / ACOS calculator — break-even ACOS and the target ACOS for a profit goal.
- Reorder-point & safety-stock calculator — when to send your next FBA shipment and how many units.
- Where is my FBA stock, and what does it trigger? — which states want you registered for sales tax.
Free for the first 50 sellers
Compare fulfillment across every product — free during early access
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