Know your real margin before you ship.
MarginSum helps independent and cross-border sellers add up product cost, freight, duty, VAT, platform and payment fees, ads and returns — so you see true profit per unit.
All tools
Amazon FBA fee calculator
2026 US fulfillment fees by size tier, weight and price band, peak and non-peak.
Shopify plan calculator
Which Shopify plan is cheapest at your monthly sales.
Stripe vs PayPal vs Shopify Payments
Card processing fees side by side, domestic or international.
Break-even ROAS & max CPA
The ad return you need before ads start losing money.
US import duty calculator
Duty, MPF and HMF for a US shipment — de minimis is suspended.
EU & UK VAT calculator
VAT-inclusive prices, the €150 IOSS limit and the UK £135 rule.
Etsy vs eBay fee calculator
Listing, transaction and payment fees and your profit on each.
WooCommerce hosting compared
Intro vs renewal prices from official pages, total cost over time.
Profit & landed cost calculator
Full per-unit profit across Amazon, Shopify and WooCommerce.
Shopify vs WooCommerce
Sourced cost breakdown, pros and cons.
Profit & landed cost
Amazon US referral fees by category, Shopify plans and Shopify Payments, WooCommerce with Stripe or PayPal. Net profit, margin, ROI and break-even price.
Calculate →Shopify vs WooCommerce
A sourced cost breakdown, pros and cons, and who should choose which.
Compare →Sourced, dated fees
Every built-in fee links to the official page and shows when we last checked it. Anything we couldn't verify stays editable.
How we source data →