A field-by-field guide to Amazon Seller Profit: what to include, what to exclude, and how to avoid unit mistakes.
Inputs are the only “truth” the model sees. Clean input definitions make outputs like net profit and margin % meaningful.
This guide helps you define selling price, product cost, fees, and shipping/fulfillment so the calculator reflects your real scenario—not a spreadsheet fantasy.
Before typing, decide whether values are monthly, annual, per-unit, or per-order. Most errors come from mixing these silently.
If you’re unsure, re-run with a simpler scenario and confirm the output direction.
Key inputs: selling price, product cost, fees, shipping/fulfillment, and ad spend.
Be consistent about units (monthly vs annual) and scope (include fees/taxes if they exist in real life).
Compare outputs like net profit, margin %, and ROI across scenarios instead of trusting one number.
If the decision changes under downside assumptions, build a buffer or revise the plan.