Use investment projections as scenarios, not promises
An investment projection combines starting balance, contributions, time and an assumed return. The result can help compare saving choices, but real markets do not deliver a constant return each year. Volatility, fees, taxes, inflation and the timing of gains and losses can materially change an outcome.
How to use this page
The calculator compounds the starting amount and adds the entered monthly contributions. It separates contributions from estimated growth. Use several return assumptions and keep contribution timing consistent when comparing scenarios.
Practical exampleRather than relying on one 8% projection, compare 4%, 6% and 8%. If a goal works only at the highest assumption, increasing contributions or extending the time horizon may create a more resilient plan.
Inputs to verify
- Use an after-fee return assumption when account expenses are known.
- Do not substitute a recent stock return for a long-term planning rate.
- Consider taxes and inflation when evaluating future purchasing power.
Common questions
Does the calculator predict the market?
No. It illustrates mathematical scenarios using the rate you provide.
Why does starting earlier matter?
More periods allow both prior growth and additional contributions to compound, though actual returns remain uncertain.
Interpret growth as a scenario, not a forecast
The useful comparison is not only the ending balance. Separate money you contributed from modeled growth, then rerun the projection with lower and higher net returns. Fees compound in the opposite direction of returns, so even a small annual fee can matter over a long horizon.
Sources and investor education
The projection uses the assumptions you enter and does not predict market performance or recommend an investment.