Savings Plan Calculator — Future Value with Regular Contributions
See how your savings grow: enter a starting deposit, regular contributions, the annual interest rate and how many years you plan to save — the calculator shows the final balance, total deposited, interest earned, and a month-by-month growth curve.
Contribution frequency
%
years
Total savings balance at the end of the period
32,703.47
totalInitial deposit
3.1%
Contributions
73.4%
Interest earned
23.6%
- 1
Period rate
5% ÷ 12 ÷ 100 = 0.004167 - 2
Total periods
10 × 12 = 120 - 3
Growth factor
(1 + 0.004167)^120 = 1.647How much one unit grows over the full savings horizon at the period rate. - 4
Future value
1,000 × 1.647 + 200 × (1.647 − 1) ÷ 0.004167 = 32,703.47
How does this calculator work?
FV = PV·(1+r)^n + PMT·((1+r)^n−1)/r. Enter an initial deposit, regular contributions, annual interest rate and years to see the total balance, interest earned, and growth curve. Compound interest accelerates strongly in later years — time in the plan is as important as the rate.
Formula
How this is calculated
The savings plan uses the standard future-value-of-ordinary-annuity formula. The initial deposit (PV) compounds at the period rate r = annual rate ÷ periods per year for n total periods. Each regular contribution (PMT) also compounds from the period it is made; the sum of all those compounded contributions equals PMT·((1+r)^n − 1)/r, the future value of the annuity stream. Adding both terms gives the total balance.
The donut chart divides the final balance into three parts: the initial deposit, the total regular contributions, and the interest earned. As the horizon or rate increases, the interest slice grows much faster than the contribution slice — this is compound growth. The area curve below shows the month-by-month balance, interpolated for quarterly and yearly contribution frequencies.
Assumptions: contributions are made at the end of each period (ordinary annuity), compounding matches contribution frequency, and the rate is constant. Inflation and taxes are not modelled; subtract an estimated inflation rate from the interest rate to approximate real purchasing power.
Frequently asked questions
Compound interest means you earn returns on previously earned returns. As the balance grows, the same percentage generates larger absolute gains each year — a 5% return on 100,000 is 5,000, while on 10,000 it is only 500. This snowball effect accelerates over time.
Yes. Monthly contributions enter the account 11 months earlier on average compared with a single year-end deposit. For the same nominal annual amount, monthly contributions produce a slightly higher final balance because more time in the account means more compounding.
The calculator shows nominal (not inflation-adjusted) values. To estimate real purchasing power, subtract your expected inflation rate from the interest rate (e.g. 5% interest minus 2.5% inflation ≈ 2.5% real return) and re-run with that adjusted rate.
TG we-Calculate Editorial Team. (2026). Savings Plan Calculator — Future Value with Regular Contributions [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/savings-plan-calculator
TG we-Calculate Editorial Team. "Savings Plan Calculator — Future Value with Regular Contributions." TG we-Calculate. 2026. https://we-calculate.com/calculator/savings-plan-calculator.
TG we-Calculate Editorial Team, "Savings Plan Calculator — Future Value with Regular Contributions," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/savings-plan-calculator
@misc{wecalculate_savings_plan_calculator, title = {Savings Plan Calculator — Future Value with Regular Contributions}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/savings-plan-calculator}}, year = {2026}, note = {TG we-Calculate} }
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