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Free Tools

Financial Calculators for
eCommerce Founders

The same financial models our fractional CFOs use with 60+ brands doing $260M+ in combined revenue — free, interactive, and running entirely in your browser. No signup required. Your data never leaves your device.

The Margin X-Ray

New

Two taps — your category and revenue band — and see the median P&L for brands exactly like yours: gross margin, CM1, CM2, CM3 and net, cents on the dollar, plus the one line quietly eating your profit.

See the benchmark →

Real Cost of Returns Calculator

New

A returned $100 order costs you $30–$40 once you stack return shipping, 3PL handling, markdown on resale, the non-refundable payment fee, and abuse drag. Run your numbers by category and see what a 3-point return-rate cut is worth in cash.

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Due Diligence Question Bank

New

Selling your brand? Every financial and legal question a buyer will ask — including the "gotcha" follow-ups. Read all 34 categories and download the free PDF.

Get the Question Bank →

Creator Incentive Model

New

For TikTok Shop and affiliate programs. Model commission and behaviour bonuses against your margin: the $5/sale creator floor, fully-loaded contribution per order, blended creator CAC, and how much bonus headroom you have before a flat 30% rate wins.

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Contribution Margin Calculator

See exactly where every dollar goes — COGS, shipping, processing, ads, and what's left as profit. Calculate your ROAS, MER, and CM3 instantly.

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Ad Spend Scaler

Figure out how much more you can spend on ads while staying profitable. Get your new blended ROAS target and a ready-to-send email for your agency.

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Maximum CAC Calculator

Calculate the maximum you should pay to acquire a customer based on your unit economics, repeat purchase rate, and desired payback period.

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Default Dead or Alive?

Will your business reach profitability before running out of cash? Enter your numbers and get a 24-month projection with a clear verdict.

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Fractional CFO ROI Calculator

New

Calculate the ROI of hiring a fractional CFO. Compare costs vs full-time, project margin improvements, and estimate your payback period in seconds.

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Break-Even ROAS Calculator

New

Calculate your break-even ROAS — the minimum return on ad spend needed to cover all costs. See your target ROAS, maximum ad budget, and break-even MER.

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Inventory Optimization AI

AI-Powered

Upload one Shopify sales report and get a 15-page inventory strategy — SKU rankings, dead stock recovery, and a 90-day action plan. Powered by Claude AI.

Get the AI Skill →

True Interest Cost

AI-Powered

Upload any cash advance offer — Wayflyer, Shopify Capital, Parafin, Clearco. Get the real APR and a full cash flow schedule in 30 seconds. Powered by the 8x AI CFO.

Reveal True APR →
How to use these tools

Start with the diagnosis, end with the cure

These calculators follow the same diagnostic sequence our CFOs use with new clients.

1

Check Your Pulse

Run Default Dead or Alive to see if your current trajectory leads to profitability or a cash crisis.

2

X-Ray Your Margins

Use the Contribution Margin Calculator to see exactly where every dollar goes — and where profit leaks hide.

3

Optimize Spend

Run the Max CAC and Ad Spend Scaler to find your profitable growth ceiling — and give your agency the right targets.

4

Optimize Inventory

Use the Inventory Optimization AI to rank every SKU, find dead stock, and build a 90-day action plan from your Shopify data.

Go deeper

Want a CFO to run these numbers on your real data?

These calculators give you the framework. A fractional CFO gives you the context, the judgment, and the execution plan. Book a free diagnostic call and we'll show you exactly where your profit leaks are.

Talk to a CFO