The payback period is the time it takes for cumulative revenue from a cohort of users to equal what you paid to acquire them ([[cac]], or [[cpi]] for a purely paid program). Plot cumulative per-user revenue against the per-user acquisition cost; the day the revenue curve crosses the cost line is the payback point. Before it, the cohort is in the red; after it, every additional dollar is profit.
It is easy to confuse with the profitability ratios, but it measures a different thing. [[roas]] tells you your return at a fixed window (D30 ROAS); [[ltv]] ÷ [[cac]] tells you lifetime return. Neither tells you when you break even. A cohort can post a healthy D365 LTV/CAC and still take ten months to pay back — both are true at once. Payback is the time dimension the ratios leave out.
Why payback period is really a cash-flow metric
You can be ROAS-positive and still cash-constrained. Spend $1M acquiring users today and recoup it over twelve months, and you have tied up $1M for a year — and to keep growing you must fund next month's spend before this month's cohort has paid you back. The shorter the payback, the faster you recycle cash into more acquisition; the longer it is, the more working capital (or outside financing) scaling demands. This is why payback period, more than any return ratio, gates how fast a company can grow on its own cash.
Days to recoup CPI at real catalog ARPDAU bands (IAP-only, US, MWM)
| Cost per install | Median app — $0.01 ARPDAU | Top-decile — $0.04 | Top-1% — $0.15 |
|---|---|---|---|
| $0.50 CPI | 50 days | 13 days | ~3 days |
| $1.00 CPI | 100 days | 25 days | ~7 days |
| $2.00 CPI | 200 days | 50 days | ~13 days |
| $5.00 CPI | 500 days | 125 days | ~33 days |
Payback = CPI ÷ ARPDAU. These use IAP ARPDAU only — most apps layer ad revenue on top, which raises blended ARPDAU and shortens payback. Even so, the matrix shows why the median app (~$0.01 IAP ARPDAU) cannot sustain paid UA on purchases alone: even a $0.50 install takes ~50 days to recoup, and a $2 install over six months. Scaling paid acquisition requires top-decile monetization or real ad revenue.
- Hyper-casual / ad-monetized: D1-D7 — fast [[arpdau]] from ads, so payback is near-immediate but volume-dependent.
- F2P games: D90-180 — early purchases plus a long whale-driven tail.
- Subscription apps: D180-365 — recurring revenue accrues slowly but predictably.
Payback period calculator
Divide your blended acquisition cost (CPI or CAC) by ARPDAU — daily revenue per active user — to see how many days a cohort takes to recoup what you paid for it.
Enter your numbers to see your result and how it compares to the catalog.
ARPDAU benchmarks: MWM catalog, IAP ARPDAU, US — median ~$0.01, top-decile ~$0.04, top-1% ~$0.15. Layer ad revenue on top for a blended ARPDAU.
Levers to shorten payback: lift early monetization (front-loaded [[iap]], faster [[trial-conversion]]), improve [[retention]] so cumulative revenue rises sooner, lower [[cac]] or [[cpi]], or shift the mix toward faster-paying cohorts and geos. Because payback gates how aggressively you can fund [[ad-spend]], shortening it is often a higher-leverage growth move than chasing a marginally better lifetime ratio.