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Compounding & Time Calculator

Explore how delay, contribution patterns, and growth rates change long-term outcomes.

Private growth lab

Compare time, not just totals.

These scenarios use annual compounding and end-of-year contributions. They illustrate tradeoffs; they do not predict investment returns.

Annual return 7.0%Total horizon 40 yearsDelay / early years 10 yearsAnnual contribution Starting lump sum

Investor A contributes for 10 years, then coasts. Investor B starts at year 10 and contributes through year 40. At 0.1%, A's early coasting path leads in this scenario.

A final value (coasts after 10y)$631,046

B final value (grinds 30y)$566,765

A total contributed$60,000

B total contributed$180,000

A/B final value ratio1.11x

Early pathLate path

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Stress-test your compounding assumptions

Save a simple prompt set for checking return assumptions, contribution levels, and time horizon.

Read the methodology, assumptions, and source notes