Profit Dollars Over Vanity Ratios

Are you maximizing profit dollars, or just protecting a comfortable ROAS?

Most founders sit on a high blended ROAS and call it discipline. Usually it is profit left on the table. This tool models your real cost curve and finds the Net Sales level that maximizes total Contribution Profit dollars, the number that actually pays your team, your inventory, and you.

The operator truth: Advertising naturally gets less efficient as you scale spend. That is not a reason to stop. As long as your next acquisition dollar returns more Gross Profit than it costs, spending more grows your total Contribution Profit dollars even while your dashboard ratios fall. Optimize the profit dollars you generate, not the ratio on the screen.

New to these terms? Read this first (60 seconds)

Contribution Profit is what remains from Net Sales after subtracting the variable costs of each sale: product cost (COGS), variable delivery expenses (pick/pack/shipping/merchant fees/returns), and the ad spend that acquired the order. It is Gross Profit minus Ad Spend.

The trap: A high Blended ROAS feels safe, but a lower Blended ROAS on a larger spend usually generates significantly more total Contribution Profit dollars. Profit dollars pay for inventory and payroll; ratios do not.

How to use this tool: Type your actual baseline numbers on the left. The chart and scenario explorer on the right model where your profit dollars peak. Hover or tap any small i icon for plain-language definitions.

Your Baseline Numbers iPull these from your accounting records and P&L. Cost of Delivery (COGS, freight, fulfillment) lives in your books, not the ad platform or Shopify.

Ad Spend iTotal media spend across all channels for the period (Meta, Google, TikTok, etc.). Blended, from your financial records. All channels, this period

Net Sales iProduct revenue after discounts and returns, excluding taxes and shipping collected. The only valid base for profit math. After discounts & returns

Product COGS % iCost of Goods Sold: Landed product manufacturing cost, inbound freight, customs, and duties as a % of Net Sales. % of Net Sales

Variable Delivery % iPick/pack, outbound customer shipping, packaging, merchant processing fees (2.9% + 30¢), and return allowance as a % of Net Sales. Pick/pack, ship, fees, returns

Total COD: 32.0% Gross Margin: 68.0%

Average Order Value iAverage Order Value (AOV): Net Sales divided by total order count. Converts revenue into customer units. AOV on initial order

Repeat Revenue / User iEstimated revenue an acquired customer generates beyond their first order over their customer lifetime. Lifetime repeat revenue

Currency Display

Advanced: Cost Curve Tuning & Fixed OPEX

The cost curve models diminishing returns: ad platforms spend your cheapest, best-converting dollars first, so each additional dollar tends to buy slightly less. Connor MacDonald's formula models this with an efficiency decay rate.

Presets:

Scale Step Size % iThe incremental revenue step size modeled in the simulation (default 5%). Net Sales step per increment

Efficiency Decay % iHow much prospecting efficiency each ad dollar keeps at the next scale step. 97% means every 5% step up in sales makes acquisition ~3% less efficient. Testing creative and landing pages keeps this higher (98-99%). Acq ROAS kept per step

Monthly Fixed Costs (OPEX) iFixed monthly operating expenses (payroll, software, warehouse rent, overhead). Used to evaluate the Lifeline Relationship: how many months of fixed overhead are covered by Contribution Profit. Fixed overhead for coverage checks

Contribution Profit vs. Net Sales

Watch total profit dollars climb as you scale spend.

Contribution Profit ($) You Are Here Profit-Max Slider Scenario OPEX Break-Even

Scenario Explorer

$480,000 (100% of today)

Baseline (Today)

Ad Spend

$120,000

Baseline

Blended ROAS / MER iBlended ROAS is Net Sales divided by Ad Spend. MER is the inverse cost ratio (Ad Spend divided by Net Sales).

4.00× / 25%

Baseline

Marginal ROAS iThe actual return on your next incremental ad dollar at this scale. As you scale, this decays. When it hits your Break-Even threshold, profit peaks.

3.04×

Next dollar return

Break-Even ROAS i1 / Gross Margin %. The minimum return required so that Gross Profit covers Ad Spend on this basis.

1.47×

Fixed floor

Initial Contribution $ iFirst-order Gross Profit minus total Ad Spend.

$206,400

Baseline

Lifetime Contribution $ iTotal Contribution Profit after counting customer repeat revenue over time.

$451,200

Baseline

Where You Are Now

Your actual baseline performance based on the inputs provided.

Net Sales

$480,000

Ad Spend

$120,000

Blended ROAS

4.00×

Marketing Cost (MER)

25.0%

Marginal ROAS

3.04×

Break-Even ROAS

1.47×

Initial Contribution Profit

$206,400

Profit-Max: Initial Order

Maximum Contribution Profit dollars if you only count the customer's first purchase.

Net Sales

$984,000

Ad Spend

$372,810

Blended ROAS

2.64×

Marketing Cost (MER)

37.9%

Marginal ROAS

1.47×

Break-Even ROAS

1.47×

Initial Contribution Profit

$296,310

Profit-Max: With Repeat (LTV)

Maximum Contribution Profit once customer repeat purchases are factored in.

Net Sales (Initial)

$1,728,000

Ad Spend

$986,450

Blended ROAS

1.75×

Marketing Cost (MER)

57.1%

Initial Contribution $

-$35,210

LTV Break-Even ROAS

0.84×

Lifetime Contribution Profit

$1,120,540

How High-Growth Brands Flatten the Cost Curve

Every eCommerce brand faces diminishing returns as ad spend scales. What separates 7-figure brands from 8-figure leaders is not avoiding scale, but systemizing how they flatten the curve.

1. Why Efficiency Decays

Ad algorithms naturally harvest the lowest-hanging fruit first. As budget increases, the auction bids on broader, colder prospects, causing Marginal Acquisition ROAS to decline.

2. How to Flatten the Curve

Continuous creative testing, dedicated landing page hooks, and diversifying across channels (Meta, Google, YouTube, TikTok) keep marginal efficiency high even as spend multiplies.

3. The Finance-First Rule

Never halt scaling just because Blended ROAS drops. Scale aggressively as long as Marginal ROAS exceeds your Break-Even threshold. That is where maximum cash is created.

ABOUT

Sourav Ghosh

Finance First Growth Operator · D2C and Omni-Channel Brands · Led marketing and growth for 1,000+ brands across 60+ countries

I have spent 10+ years in eCommerce growth across 1,000+ brands. I work as a Finance First Growth Operator for D2C and Omni-Channel Brands, typically those spending $1M+/quarter on advertising.

After a decade running an agency, I now work directly with a small number of brands on finance-first operating systems, team coaching, and profit-first spend decisions. No vanity metrics. No agency bloat.

Connect

@souravghosh LinkedIn Reddit Substack

Book an Operator Diagnostic