Investment Growth Calculator

See a year-by-year projection of contributions versus compound growth, and how a small increase in the monthly amount changes your end balance.

How it works

Balance(year n) = Balance(n−1) × (1 + r) + annual contributions. Growth share = (final balance − total contributed) ÷ final balance.

Worked example

$300/month at 8% reaches about $447,000 in 30 years. Raising it to $400 adds roughly $149,000 — the extra $100 compounds into 33% more wealth.

Frequently asked questions

When does growth overtake contributions?

Usually between years 12 and 18 at 7–8% returns. That crossover point is when the portfolio starts earning more per year than you add.

Should contributions rise with inflation?

Yes. Indexing your monthly amount to salary growth of 2–3% a year typically adds 25–35% to the final balance versus a flat contribution.

How do market crashes affect the projection?

Sequence matters: a crash early is recoverable and even helpful for buyers, while one in the final five years does the most damage — which is why allocations de-risk near the goal.