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Curtis Howland

Your CPA is lying to you.

Meta's blended CPA hides the real cost of your next conversion. Every dollar you add costs more than the last. This tool shows you exactly where profit peaks, where you're burning cash, and what to do about it.

Your Numbers

$

The CPA Meta reports — includes organic conversions

$

Profit per order before ad costs — your break-even CPA

$

Assumptions

70%

30% organic / would have happened anyway

10%100%
0.65

Moderate — typical for most Meta accounts

Heavy (0.2)Mild (0.95)

Derived

True Paid CPA$57.14
Paid Conversions/day52.5
Marginal vs Avg CPA1.54x

Recommendation

Increase spend by $208/day

+$2/day profit ($60/mo)

Move from $3,000 to $3,208/day to hit peak profit.

Peak Profit Spend

$3,208

/day

Peak Daily Profit

$1,727

/day

Break-Even Spend

$10,984

/day

Your Daily Profit

$1,725

at $3,000/day

Monthly Ad Spend

$90,000

Monthly Profit

$51,750

Monthly Profit Left on Table

$60

You're in the profitable growth zone. Every incremental dollar makes money.

Your marginal CPA is $87.91, below your $90.00 break-even. You could push to $3,208/day before hitting max profit.

Avg CPA
Marginal CPA
Total Profit

Spend Breakdown

SpendConversionsAvg CPAMarginal CPAProfit
$28611.4$25.09$38.60$739
$85723.2$36.85$56.70$1,236
$1,42832.4$44.07$67.80$1,488
$1,99940.3$49.58$76.27$1,630
$2,57047.5$54.13$83.28$1,703
$3,142PEAK54.1$58.07$89.34$1,727
$3,71360.3$61.57$94.72$1,714
$4,28466.2$64.73$99.59$1,672
$4,85571.8$67.63$104.05$1,606
$5,42677.2$70.31$108.18$1,519
$5,99882.4$72.82$112.03$1,415
$6,56987.4$75.18$115.66$1,295
$7,14092.2$77.40$119.08$1,162
$7,71197$79.52$122.33$1,017
$8,282101.6$81.53$125.43$860
$8,854106.1$83.46$128.39$694
$9,425110.5$85.30$131.24$519
$9,996114.8$87.08$133.97$335
$10,567119$88.79$136.60$144
$11,138123.2$90.44$139.14-$54
$11,709127.2$92.04$141.59-$259
$12,281131.2$93.58$143.97-$470
$12,852135.2$95.08$146.28-$687
$13,423139$96.54$148.53-$910
$13,994142.9$97.96$150.71-$1,137

The math behind the curtain

This uses a power function model: Conversions = a × SpendB. You set B as a scenario assumption. Real-world data is noisy — creative fatigue, seasonality, auction dynamics all muddy the signal. Modeling scenarios beats pretending you have clean data.

The key insight: marginal CPA is always average CPA ÷ B. At B=0.65, your marginal CPA is 54% higher than Ads Manager shows. That gap is the hidden cost of scale that most advertisers never see.

Profit peaks where marginal CPA equals your contribution margin. Past that point, every new conversion loses money — but you're still net positive until break-even. The space in between is where the real strategy decisions happen.

Curtis Howland

Performance marketing tools & strategy