Verimargin — Amazon FBA Profit & Fee Calculator

About

See your real FBA profit before you source — right on the product page.

Verimargin overlays every Amazon product page with the numbers that decide a sourcing call: referral fee, FBA fulfillment fee, monthly storage fee, net profit, margin, and ROI. Enter your cost once — it's remembered per product.

Built for accuracy.

Fee math verified against Amazon's own FBA Revenue Calculator
2026 US fee schedule (effective January 15, 2026; re-verified each release), including Amazon's marginal "portion of price" referral brackets that most calculators get wrong (Electronics Accessories, Jewelry, Furniture, Watches, Fine Art, Appliances)
Models Amazon's 3.5% fuel & logistics surcharge on fulfillment fees (effective April 17, 2026) as its own line item — just like your settlement report — so your fulfillment cost isn't understated
Honest about uncertainty: when a page doesn't expose package dimensions or a fee category can't be matched, Verimargin tells you instead of guessing silently
Fast and focused.

Works on standard, variation, bundle, out-of-stock, and Subscribe & Save pages
Size-tier classification (Standard / Bulky / Extra-Large) from page data
Per-product category override + default category setting
Quick-links to Keepa, CamelCamelCamel, and Seller Central for deeper research
Light/dark/auto theme
Private by design.

100% client-side — no servers, no account, no analytics, no tracking
Your costs (COGS) are stored only in your browser
Reads only the Amazon product page you're viewing
Free. The core calculator is free, forever. (Pro features may come later — the free tier stays.)

Made for FBA sellers, resellers, and arbitrage sourcing on amazon.com.