Growth Economics

Does growth pay for itself?

Change any input — every metric, chart and recommendation recalculates.

Synthetic Demo Data — Not MacPaw Actuals

Inputs

Eney · USD · 30-day window

Ad spend$30,000

Trial → paid19.0%

Total acquisition cost ($)Ad spend ($)ImpressionsClicksTrial signupsNew paid customersAttributed revenue ($)Subscription price ($/mo)Avg monthly revenue / customer ($)Gross margin (%)Monthly churn (%)Forecast horizon (months)Target CAC ($)Assumed incremental revenue ($)

CTR

1.20%

CPC

$0.89

CPM

$10.71

Trial CVR

6.50%

Ad-only CAC

$72

Blended CAC

$87

Target $85

ROAS (attributed)

0.58×

Simplified LTV

$128

Contribution / churn

LTV : CAC

1.5×

CAC payback

7.9 mo

ROMI (incremental)

-9%

Uses assumed incremental revenue

Contribution (24 mo)

$10,992

AI Budget Advisor

Deterministic rules: CAC ≤ target, LTV:CAC ≥ 3, payback ≤ 12 mo, CTR vs. conversion quality

Demo AI · rules · template-based

Hold & optimise

Blended CAC $87 is above the $85 target.
LTV:CAC of 1.5× is under the 3× guideline.

Assumes the inputs reflect one cohort and attribution window. A recommendation, not an action — budget changes require human approval.

CAC payback

Cumulative contribution per customer (with churn) vs. blended CAC

LTV sensitivity to churn

How fragile is the LTV assumption?

Best / base / downside

Downside: −20% paid, +25% churn · Best: +20% paid, −20% churn

Channel budget allocation

Splits the $30,000 ad spend · assumes diminishing returns per channel

Meta · 35%$10,500 → 114 paid · CAC $92

Google Search · 40%$12,000 → 232 paid · CAC $52

YouTube · 15%$4,500 → 44 paid · CAC $103

LinkedIn · 10%$3,000 → 15 paid · CAC $200

Modelled total: 405 paid customers. Illustrative response curve, not a forecast.

Scenario A vs. Scenario B

Why the campaign with cheaper clicks isn't automatically the one to scale

	A · Higher CTR, lower quality	B · Lower CTR, higher retention
CTR	1.80%	0.90%
CPC	$0.56	$1.11
Blended CAC	$79	$88
Monthly churn	15.3%	6.4%
Simplified LTV	$71	$188
LTV : CAC	0.9×	2.2×
24-mo contribution	$-2,846	$17,004

A wins on CTR and CPC. B creates more contribution over 24 months because retention compounds. Judge campaigns on customer value, not click cost.

Formula notes

CTR = Clicks / Impressions

CPC = Ad Spend / Clicks

CPM = Ad Spend / Impressions × 1,000

Trial CVR = Trials / Clicks

Ad-only CAC = Ad Spend / New Paid

Blended CAC = Total Acquisition Cost / New Paid

ROAS = Attributed Revenue / Ad Spend

LTV = (ARPU × Gross Margin) / Monthly Churn

Payback = Blended CAC / Monthly Contribution

ROMI = (Incremental Revenue × Margin − Spend) / Spend

Simplified LTV assumes stable revenue, constant churn and stable margins. ROMI requires an explicit incremental-revenue assumption — attributed revenue is not proven incremental revenue. Zero denominators display "—".