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Ecommerce unit economics, made usable

Know your margin
before you scale it.

Free calculators for pricing, fees, advertising, sourcing and operations. Every assumption is editable. Every formula is explained.

10 focused calculators 0 accounts required 100% editable inputs
Example order Modeled
Net profit $14.82 24.7% margin
Revenue$60.00
Product + logistics−$30.00
Fees + returns−$7.18
Acquisition−$8.00
Price and product cost are the highest-impact levers in this example.
For marketplace sellers DTC operators Print-on-demand brands Wholesale makers Lean ecommerce teams
Start with the decision in front of you

Useful tools, not filler pages.

Each calculator has a distinct formula, worked example, limitations and update note. The site is designed around decisions sellers already need to make.

Marketplace fees

Etsy Profit

Estimate Etsy transaction, payment, listing, Offsite Ads and country-specific fees, then see profit, margin and the break-even item price.

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Advertising

Break-even ROAS

Calculate the maximum CPA and minimum ROAS that keep an ecommerce order at break-even after product, shipping, payment and return costs.

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Unit economics

Product Margin

Calculate gross margin, contribution margin, markup, net profit per order and break-even price with fees, shipping, returns and acquisition cost included.

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Store economics

Shopify Profit

Estimate monthly Shopify operating profit from revenue, orders, COGS, payments, fulfillment, returns, apps, fixed costs and advertising.

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Sourcing

Landed Cost

Estimate landed cost per unit from goods, freight, insurance, customs value, duty, import tax, brokerage, port, inspection and domestic delivery.

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Operations

Return Impact

Estimate monthly profit lost to ecommerce returns, cost per return, margin after returns and the return rate that would consume gross profit.

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Pricing

Wholesale Price

Calculate wholesale list price, discounted invoice price and suggested MSRP while preserving maker margin after commission, overhead and MOQ discounts.

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Shipping

Dimensional Weight

Compare actual and dimensional weight for one or multiple packages with an editable divisor in metric or imperial units.

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Inventory

Reorder Point

Calculate reorder point, safety stock, days of inventory and a case-pack-rounded order quantity from demand, lead time and review period.

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Pricing

Discount Profitability

Compare baseline and promotional profit, calculate required unit uplift, and estimate the maximum discount supported by your projected volume increase.

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The operating loop

From rough assumption to better decision.

The calculators are intentionally simple enough to use in minutes and structured enough to become a weekly operating habit.

  1. 01

    Enter your real costs

    Start with defaults, then replace every material number with a statement, invoice or recent operating average.

  2. 02

    Find the binding constraint

    Use the result and cost breakdown to see whether price, product, shipping, fees, returns or acquisition is doing the damage.

  3. 03

    Test one lever at a time

    Make a controlled change, measure profit per visitor or order, and update the model with realized data.

profit = revenue
  − product_cost
  − fulfillment
  − fees
  − expected_returns
  − acquisition_cost
Built for trust

The AI never owns the math.

All financial outputs come from deterministic, testable Python formulas. An optional paid report can use OpenAI to organize findings and actions, but it receives the completed calculation and is instructed not to alter a number.

  • Server-rendered pages for speed and discoverability
  • Rate fields stay editable when platforms change
  • Source-monitoring workflow flags official fee-page changes
  • No comments, profiles, uploads or moderation queue
Read the methodology
Begin with the universal model

Is the next order actually worth winning?

Calculate fully loaded profit per order before increasing ad spend, accepting a discount or adding another sales channel.

Run the margin calculator