What could a retirement balance become with regular contributions?
A retirement projection compounds an existing balance and a stream of future contributions over a long horizon. Because the term is long, small changes in rate or contribution can create large differences.
Two compounding streams across the horizon
Years = Retirement age − Current agei = Annual return ÷ 100 ÷ 12, n = Years × 12Future = Saved × (1 + i)ⁿ + Monthly × [((1 + i)ⁿ − 1) ÷ i]Monthly income shown uses a 4% annual withdrawal rate.A long-term contribution projection
The default case grows current savings and repeated contributions for the entered number of years, then separates contributed money from projected growth.
Illustrative inputs; currency amounts below use USD. Rates and prices are assumptions, not live quotes.
- Current age
- 34
- Retirement age
- 65
- Saved so far
- $45,000.00
- Monthly contribution
- $500.00
- Annual return
- 6%
Step-by-step calculation
- Saving horizon = retirement age 65 − current age 34 = 31 years, or 372 months.
- Compound the initial 45,000 and each end-of-month 500 contribution at monthly rate 0.005. Projected balance = 827,134.998606.
- Illustrative monthly withdrawal = 827,134.998606 × 4% ÷ 12 = 2,757.116662. This arithmetic does not test whether withdrawals are sustainable.
Intermediate figures are rounded for reading. Results use the full calculation precision.
Contributed capital versus modelled growth
Read the final balance together with total contributions. The gap between them is modelled growth, which is highly sensitive to rate and time assumptions.
Inflation and income questions outside the balance
A nominal ending balance does not show future purchasing power or sustainable retirement income. Inflation and withdrawal planning require separate calculations.
- The return and contribution remain constant for the full term.
- Contributions follow the timing shown in the formula.
- Inflation, tax, fees, salary changes and withdrawals are excluded.
Calculations related to retirement savings
The following tools examine neighbouring parts of the same calculation without changing the inputs or assumptions used above.
References
Sources and conventions
- SEC Investor.gov: compound growth
A comparison tool for compound growth assumptions, not a promised investment return.
Quick answers
Frequently asked questions
What does the 4% monthly income figure mean?
It is the projected balance multiplied by 4% per year and divided by 12; it is not a guaranteed sustainable income.
Are retirement results adjusted for inflation?
No. The displayed future value is nominal under the entered return rate.
What happens if retirement age is below current age?
There is no positive saving period, so a meaningful forward projection cannot be produced.
Calculation method and limitations · Report an error
Educational content only. This guide is not financial advice.