Ecommerce Guides
In-depth technical guides, cost breakdowns, and pricing strategies for online store owners, physical product brands, and retail buyers.
In-Depth Guides
Gross Margin vs Net Profit in Ecommerce: Why 60% Becomes 16%
Understand why a healthy gross margin shrinks to a thin net profit once fees, shipping, ads, and returns are counted, and how to protect the number that reaches your bank.
Amazon FBA Fees Explained (2026): Referral, Fulfillment and Storage
A plain-English breakdown of the three Amazon fee layers that decide your FBA profit: referral fees by category, per-unit fulfillment fees by size, and monthly storage.
How to Price a Product for Profit: A Step-by-Step Framework
A repeatable framework for pricing physical products so the price actually covers COGS, fulfillment, fees, ads, and returns, and still leaves a healthy margin.
The True Cost of Free Shipping (And How to Offer It Profitably)
Free shipping lifts conversion but silently eats margin. Learn how to set a free-shipping threshold that pays for itself and when to bake shipping into the price instead.
ACoS vs TACoS vs ROAS: The Ad Metrics That Decide Your Profit
What ACoS, TACoS, and ROAS each measure, how they relate, and how to find your break-even ACoS so you know exactly how much you can spend on ads and still profit.
More Topics & Deep Links
Gross Margin vs. Net Profit in Ecommerce
Learn why an apparent 60% gross margin on paper can shrink to a 16% net profit margin after accounting for shipping, gateway fees, ad spend, and refunds.
Hidden Ecommerce Costs: The 7-Tier Expense Sequence
A complete breakdown of unrecovered postage subsidies, custom mailers, fixed app stack allocations, and return allowances per order.
Shopify Payments Credit Card Rates & App Allocations
Understand Shopify plan fee tiers (Basic, Shopify, Advanced) and learn how to allocate monthly app subscriptions per order.
Initial Margin (IMU) vs. Maintained Margin (MMU)
How retail buyers set initial sticker markups to protect net profit against inventory shrinkage and end-of-season clearance markdowns.
The B2B Wholesale Pricing & MSRP Waterfall
Side-by-side analysis of manufacturer gross margins versus retailer keystone 50% margins when pitching physical stockists.
Unit Break-Even Volume & Sales Revenue Thresholds
Mathematical formulas for calculating contribution margin per unit and total monthly order volume required to cover fixed overhead.
MerchSites Calculation Methodology & Math Standards
Technical documentation detailing our big.js floating-point precision math, decoupled calculator architecture, and fee benchmarks.
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MerchSites tools and guides are written and reviewed by ecommerce practitioners. Calculations are cent-accurate estimations based on reported platform fees and standard formula math.