Free calculators for online sellers.
Free calculators for online sellers, each with the formula shown. Pricing a product? Work out profit per unit after fees, on any marketplace or on eBay, Etsy and Amazon with their own fee fields. Importing stock? Get the landed cost of every unit. Closing a month? Calculate cost of goods sold. Self-employed? Estimate self-employment tax and quarterly estimated tax payments at 2026 rates. Each one links to a full answer.
SAMPLE · DEMO STORE · NOT A CLIENT
Marketplace profit calculator
Price, item cost, shipping, fees and ads — your profit per unit, margin and break-even price.
Open the calculator →Answer Use landed cost as your item cost: what is landed cost?
Landed cost calculator
Supplier price, freight, duty and fees — the real cost of every unit, and what it does to margin.
Open the calculator →Answer What is landed cost? The formula and a worked example
COGS calculator
Beginning inventory, purchases and ending inventory — cost of goods sold and gross margin.
Open the calculator →Answer How to work out cost of goods sold for an online store
The same numbers, every month.
A calculator answers one question once. Our monthly e-commerce bookkeeping answers them every month: landed cost, inventory, cost of goods sold and marketplace fees kept current, so you see profit by channel without doing the math.
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