Performance marketing for AI-era growth – backed by models, not gut feeling.

What is one subscriber worth?

Terms used on this page

LTV M13 – lifetime value over 13 months: the first payment, 12 months of renewals and the first annual renewal · RC – RevenueCat; SOSA – its State of Subscription Apps report · SBP – Apple's Small Business Program (15% commission under $1M/year; Google has the same 15% tier) · PSP – payment service provider on web checkout (Stripe, Paddle) · CPA – cost per new subscriber · ROAS – net LTV ÷ CPA · M1 / M6 / M12 – share of a monthly cohort still paying at that renewal · a2a / w2w – app-store billing / web-checkout billing (the web cohort retains ×0.89 on benchmarks).

How to use – 30 seconds
  1. Pick your vertical (refund rate, typical plan mix) and geo (VAT default – and a reminder to enter local prices). Retention benchmarks come from RevenueCat SOSA 2026; the scenario preset moves them P25 → P75.
  2. Enter your plans and prices – the only thing the tool can't know. 1st-period price if you run an intro offer; shares must sum to 100%.
  3. Retention: keep the benchmark curve and type over any anchor you have (M1 / M6 / M12, weekly renewals #1–#3, week-26 survival) – a typed field turns blue and is used as-is – or, if you only have two renewals so far, switch to Fit from my first 2 renewals. Where each number lives in your own systems – Reference › Data sources.
  4. Press Calculate (the default case is already computed). Enter your CPA – from Ads Manager or the Unit Economics Calculator – to see ROAS, payback month, target CPA and peak cash. Show a colleague your exact setup – Copy share link.

Setup

Plans & prices (your data – required; mix must sum to 100%)

PlanOnPrice, $1st-period price, $ (intro offer – optional)1st price, $Share of subscriptions, %Share, %
Weekly$$%
Monthly$$%
Yearly$$%
1st-period price: what the first payment is charged at (e.g. $8.99 for the first week/month, $59.99 for the first year); every renewal is charged at the plan price. Leave blank when there is no intro offer.

Retention & renewals

From sticker price to net revenue

Order of deductions
  • Refund hits the first payment only (renewals are rarely refunded) – it is inside the gross figure.
  • VAT / GST is stripped out of the sticker price first – the store (or you, on web) remits it; then the store commission or PSP fee is taken from what is left.
  • Web cohort ×0.89 [B, Adapty] applies to benchmark retention on web billing only – typed or fitted renewals already are your cohort.
  • Upsells & offers scale every payment (default 0). Details: design decisions §9.

Results

Press Calculate to compute the results with the current inputs.
…
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Blended net LTV M13
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Gross LTV M13 (sticker)
–
VAT · fee · cohort
–
Net from the 1st payment (M0)
$
$
CPA from Ads Manager (cost per subscription / purchase) – or the modeled CPA of the Unit Economics Calculator. Leave blank to see LTV alone.
–
ROAS (net LTV ÷ CPA)
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Payback month (net)
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Target CPA (at ROAS goal)
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Break-even CPA (ROAS 1.0)

Per plan – one subscriber on that plan, M13 horizon

Cumulative net revenue per subscriber, M0 → M12

Blended (solid) and each active plan; the yearly renewal lands in the last bucket (M13 → M12+). Dashed red line = your CPA – where the blended curve crosses it is the payback month.

Sources · public benchmarks only (RevenueCat SOSA 2026 and RC's renewal-rate and billing-churn posts, Adapty 2026), re-verified against the live pages on 4 Sep 2026 – see the why? on each field and verify before big bets. Fields tagged A are documented assumptions pending research. No client data anywhere in this tool. Where each input lives in your own systems – Reference › Data sources.

✓ Run the built-in self-test 24 assertions, live in your browser

All sources – 8 links

RevenueCat SOSA 2026 · RC renewal rates by category · RC – Google Play billing-error churn · Adapty SOIS 2026 · Adapty paywall data (web cohort, welcome offers) · Adapty – price localization · Google Play – tax rates & VAT by country · Apple – price and tax updates.

About the author

Maria Atamanova – Senior Growth & Performance Marketing Manager and applied mathematician; twelve years growing businesses – apps, e-commerce, EdTech, AI data platforms – on numbers, not gut feeling.

“Does the growth math close?” is asked on every product, so it deserves one model that is sourced and tested rather than rebuilt from scratch. This one was proven on real work – Praktika, Toloka, Growth That Doesn’t Lie to Itself.

Hiring a senior growth or performance lead? See the case studies · hello@mariascales.com · LinkedIn