Inputs

Real numbers in, real margins out.

Product cost structure

API cost per active user / month (USD) e.g. 0.85 Infrastructure cost / user / month (USD) hosting, storage, bandwidth Payment processor fee (%) stripe ~2.9

Pricing assumptions

BYOK price (USD / month) one-time or subscription Bundled price (USD / month) includes API costs Hybrid base price (USD / month) small base + BYOK API

Churn and LTV

Monthly churn rate (%) BYOK typically 2-5%, bundled 5-8% Customer acquisition cost (USD) paid + organic blended

ii.

Results

Per-user economics across three pricing models.

BYOK

Lean

Gross margin 88%

Revenue / user$9.00

COGS / user$0.38

Net / user$8.36

LTV (churn-adjusted)$209

LTV / CAC5.97x

Users for $50K MRR5,556

Bundled

Familiar

Gross margin 87%

Revenue / user$29.00

COGS / user$1.81

Net / user$26.35

LTV (churn-adjusted)$329

LTV / CAC9.40x

Users for $50K MRR1,724

Hybrid

Mixed

Gross margin 91%

Revenue / user$14.00

COGS / user$0.53

Net / user$13.06

LTV (churn-adjusted)$326

LTV / CAC9.33x

Users for $50K MRR3,571

Bundled wins on revenue per user; BYOK wins on margin and trust. Hybrid sits in the middle, slightly ahead on margin because the API cost is the customer's. Pick BYOK if onboarding friction is manageable. Pick bundled if your audience does not want to think about API keys. Hybrid is rarely the wrong call; rarely the strongly right one either.

Notes on the math. Gross margin = (revenue minus COGS) over revenue, where COGS = API cost + infrastructure + processor fee. LTV = (net per user) / (monthly churn rate). Users for target MRR = target / net-per-user, rounded up. Hybrid assumes the base price covers infrastructure with the user paying API cost directly (so the only COGS on you is the base-cost portion + processor fee). All numbers are per-customer; aggregate revenue, taxes, and shared overhead are out of scope here. This is a planning calculator, not an accounting system.