Why Amazon's calculator under-reports your true cost
Seller Central's revenue calculator covers referral + FBA fees but ignores PPC, returns, long-term storage surcharges, and the 4Q peak storage premium. Real-world net margin is typically 8–12 points lower than what their tool shows.
The 30% rule (and why aggregators use it)
FBA aggregators (Thrasio, Perch, etc.) won't buy ASINs below ~30% net margin and ~30% ROI on COGS. If you can't clear both, you're working for Amazon — not building equity. Private-label products at the right price point routinely hit 25–35% net margin.
PPC ACoS — what's actually healthy
ACoS = Ad Spend ÷ Ad Sales. A 22% ACoS means you spent $22 for $100 of ad-attributed sales. For private-label, target ACoS = (1 − net margin − 5% buffer). Above that, ads bleed profit. Below 15% usually means you're under-spending.
Related guides
Long-form playbooks on the same topic, written by the RevenueLab editorial team.
Amazon FBA Fees Explained: A Sellers' Guide to Real Unit Economics in 2026
Referral fees, FBA fulfillment, storage, returns, and ad spend — the line items that turn a 'profitable' Amazon SKU into a money loser, and how to model them honestly.
Read the guideAmazon FBA Profit Guide 2026: Real Margins After Referral, FBA Fees, PPC, and Returns
Why Seller Central's calculator under-reports your true cost, the 30% ROI rule aggregators use, and the levers that actually move FBA margin.
Read the guideeBay Seller Fees Explained 2026: The True ~17% Take Rate and When to Subscribe to a Store
FVF, the $0.30 fixed fee, payment processing, and Promoted Listings — line-by-line — plus the exact volume where a Basic/Premium/Anchor Store pays for itself.
Read the guideFAQ
What's a good profit margin on Amazon FBA?
20–30% net margin after referral, FBA, storage, PPC, and returns is healthy. Below 15% is dangerous; one fee hike or PPC bid war kills it.
How much does Amazon take per sale?
Standard: 15% referral + $3.86+ FBA fulfillment + ~$0.35/mo storage. All-in including PPC, expect Amazon to keep ~35–45% of gross sale price.
Does Amazon FBA still work in 2026?
Yes, but margins are tighter than 2020. Winners use differentiated products, brand registry, off-Amazon traffic, and tight inventory turns. Generic me-too products from Alibaba are squeezed by China-direct sellers.
What's the FBA fee for small standard items?
Small standard (<1 lb): $3.86. Large standard (1 lb): $5.40+. Oversize: $9.50–$60+ depending on dimensions. Check Seller Central for current schedule.
How this calculator is built
Independently maintained
Written by Sam Doshi and the RevenueLab editorial team. We don't sell the data feeds this tool is built on.
Sourced from primary data
Benchmarks come from public AdSense / Stripe / IRS disclosures and reader-submitted data — never third-party "$X per view" claims. Full methodology.
Last reviewed
June 2026. We re-check every figure on the platform on a rolling quarterly cycle.
Editorial standards
See our editorial policy and disclaimer. Results are estimates, not advice.