Simple Savings Calculator
Enter your starting balance, monthly contribution, annual interest rate and number of years to see your projected final savings balance, total deposits, and interest earned.
%
years
Total balance at the end of the savings period
- 1
Monthly rate
5 % ÷ 12 ÷ 100 = 0.004167 - 2
Total months
10 × 12 = 120 - 3
Growth factor
(1 + 0.004167)ⁿ = 1.647 - 4
FV of initial deposit
1,000 × 1.647 = 1,647.01 - 5
FV of contributions
100 × (1.647 − 1) ÷ 0.004167 = 15,528.23 - 6
Final balance
1,647.01 + 15,528.23 = 17,175.24
How does this calculator work?
Final balance = P(1+r)ⁿ + PMT((1+r)ⁿ−1)/r, where r = monthly rate and n = total months. Enter initial deposit, monthly contribution, annual interest rate and years to project the final balance, total deposited, and interest earned. Interest compounds monthly.
Formula
How this is calculated
The calculator compounds interest monthly. Your initial deposit P earns compound interest and grows to P × (1 + r)^n after n months, where r = annual rate ÷ 12. Each monthly contribution PMT also earns compound interest from the month it is deposited; the future value of all those contributions is PMT × ((1 + r)^n − 1) / r — the standard future-value-of-an-annuity formula. Adding both components gives the total balance.
If you set the annual rate to 0 %, the calculator simply adds contributions: P + PMT × n. The month-by-month curve shows how interest accelerates growth in later years — the classic hockey-stick shape of compounding.
This is a mathematical estimate based on a constant rate and regular end-of-month contributions. Real savings accounts may carry fees, promotional rate changes, or irregular deposit schedules — use this as a planning tool and confirm exact figures with your bank.
Frequently asked questions
Interest is compounded monthly: each month the full outstanding balance (principal + all accumulated interest) earns (annual rate ÷ 12) in new interest. Your monthly contributions are also subject to compounding from the month they are deposited.
"Total deposited" is the money you personally put in — your initial amount plus every monthly contribution. The difference between the final balance and total deposited is the interest the bank credited. The higher the rate and the longer the term, the larger that gap becomes.
Set the final balance you want to reach as a target and adjust the monthly contribution field upward until the projected final balance matches your goal. You can also experiment with the rate or term to see the trade-offs.
Also known as
TG we-Calculate Editorial Team. (2026). Simple Savings Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/simple-savings-calculator
TG we-Calculate Editorial Team. "Simple Savings Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/simple-savings-calculator.
TG we-Calculate Editorial Team, "Simple Savings Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/simple-savings-calculator
@misc{wecalculate_simple_savings_calculator, title = {Simple Savings Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/simple-savings-calculator}}, year = {2026}, note = {TG we-Calculate} }
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