Unit Economics Simulator

Model your store's full unit economics: contribution margin per order, monthly P&L, break-even orders, and what a 0.5% fee change is really worth — shareable by URL.

Blended: total ad spend ÷ total orders.

Refunded orders; costs revenue but not product for simplicity.

Software, salaries, rent, subscriptions.

Per-order margin waterfall

AOV
$80.00
COGS
−$28.00
Shipping
−$7.00
Payment fees
−$2.62
Ads (CAC)
−$18.00
Returns
−$3.20
Contribution
$21.18
Contribution margin per order$21.18 (26.5%)
Monthly revenue$48,000.00
Monthly contribution$12,708.00
Fixed costs−$9,000.00
Monthly profit$3,708.00
Break-even orders per month425
What each lever is worth (per month)
Payment fee −0.5%+$240.00
COGS −5% of AOV+$2,400.00
CAC −10%+$1,080.00
AOV +$5 (same costs)+$2,793.00

Your inputs are encoded in the URL — nothing is stored on a server.

Deep-dive any lever: payment fees, CAC & LTV, ad breakeven, or fixed-cost break-even.

Runs fully in your browser — models are shared via URL, never stored.

Frequently asked questions

What are unit economics?

The profit math of a single unit of business — for ecommerce, one order: revenue minus COGS, shipping, payment fees, acquisition cost, and returns. If the contribution per order is positive and covers fixed costs at your volume, the business works; no amount of scale fixes negative unit economics.

What is contribution margin?

What is left of an order after all variable costs — the amount each order "contributes" toward fixed costs and profit. Monthly profit = contribution per order × orders − fixed costs, which also gives your break-even order count.

How do I share my model?

Click "Copy shareable link" — every input is encoded in the URL, so anyone opening the link sees your exact model. Nothing is stored on a server; the URL is the save file.

Which lever should I pull first?

The sensitivity table shows what each is worth on your numbers, but the pattern is consistent: payment fees and COGS improvements are pure margin with no demand risk, AOV increases are next (upsells, bundles), and CAC cuts are the hardest to sustain. Small percentages on every order compound into real money.

Embed this calculator

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  src="https://stopbyte.com/embed/unit-economics-calculator"
  title="Unit Economics Simulator by StopByte"
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<p>Calculator by <a href="https://stopbyte.com/tools/unit-economics-calculator">StopByte Unit Economics Simulator</a></p>