Savings & compound
interest calculator
Explore how a starting balance and regular monthly savings could grow over time.
Plan ahead · Savings growthBuild your savings scenario
A mathematical projection, not a guaranteed return. Actual savings rates can change.
More clarity, one calculation at a time.
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Open calculator ↗How to use this calculator
- Enter your starting savings balance.
- Add the amount you plan to save at the end of each month.
- Choose a hypothetical fixed nominal annual interest rate.
- Select a whole number of years and compare contributions with projected interest.
How monthly contributions build your savings
Start with $1,000 and add $100 at the end of every month for one year. With 0% interest, the ending balance is $2,200. With a fixed 6% nominal annual rate compounded monthly, it is approximately $2,295.23: $2,200 contributed and $95.23 in interest.
| Starting balance | Monthly deposit / period | Projected balance |
|---|---|---|
| $1,000 at 0% | $100 / 1 year | $2,200.00 |
| $1,000 at 6% | $100 / 1 year | $2,295.23 |
| $0 at 0% | $200 / 5 years | $12,000.00 |
Contributions are your own deposits, including the starting balance. Interest is the amount earned above those contributions. Inflation, taxes, fees, deposit timing and changing rates can affect actual outcomes.
How this calculator works
This projection compounds interest monthly and adds your contribution at the end of each month. The interest rate and deposits stay constant throughout the scenario. It does not include fees, taxes or inflation.
Try different inputs to compare scenarios. Results are estimates for general information.
A few helpful answers.
When are contributions added?
At the end of every month, after that month’s interest is calculated.
Is the rate an APY?
No. Enter a nominal annual interest rate. The tool divides it by 12 for monthly compounding.
What if the interest rate is zero?
The result is simply your initial balance plus all monthly contributions.
What is compound interest?
Compound interest means later interest is calculated on both your deposits and interest already added to the balance. This tool compounds monthly.
Does the calculator account for taxes or fees?
No. Results are before taxes, account fees and inflation. Treat the assumed interest rate as a scenario, not a product offer.