Amazon FBA vs FBM Calculator
Cost per unit against the Prime conversion lift.
Amazon revises fee schedules at least annually and adds new surcharges more often. These defaults are a starting point — the figures in your own fee preview are the ones that describe your ASINs.
Better on these numbers
FBA
by $1,945 a month
FBA costs $2.75 more per unit but the Prime badge sells 20% more of them, which wins by $1,945 a month. The conversion lift is the whole argument — without it, self-fulfilment is almost always cheaper per unit.
How the Amazon FBA vs FBM Calculator works
Self-fulfilment is almost always cheaper per unit. FBA wins on conversion, because the Prime badge sells more of them — so the comparison is not about cost at all, it is about whether the volume lift covers the cost gap.
Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price — check the platform's current fee schedule before you price a product against it. This is not tax or business advice.
Frequently asked questions
Is FBA cheaper than shipping myself?
Usually not per unit, once you account for your own negotiated shipping rates. FBA earns its cost through the Prime badge, faster delivery promises and better placement in search.
How much does the Prime badge lift conversion?
Reported lifts vary widely by category, commonly in the 20% to 50% range for competitive products. It is largest where several sellers offer the same item and smallest for unique products with no alternative.
Can I do both?
Yes, and many sellers do — FBA for fast movers where the badge matters, FBM for bulky, slow or seasonal items where storage would eat the margin. Seller Fulfilled Prime offers the badge without FBA, at the cost of strict performance requirements.
What does FBM cost that I might forget?
Pick and pack labour, packaging, the customer service burden, and the performance risk — late shipments and negative feedback affect your account health in ways FBA absorbs for you.