Inputs
$
$
Period depends on compounding frequency.
Tip
Change Compounding frequency to match your product. The Contribution per period should align to that frequency.
Projection Chart
Nominal vs Real (inflation-adjusted)Results by Year
| Year | Contributions | Interest | Taxes | Ending Balance | Real Balance |
|---|
Example Scenarios (for reference)
| Label | Initial | Contribution/Period | APR % | Freq | Years | Step-up % | Inflation % | Tax % | Contribute at Start |
|---|---|---|---|---|---|---|---|---|---|
| Starter plan | 1000 | 100 | 6 | 12 | 10 | 0 | 2 | 0 | No |
| Aggressive saver | 2500 | 300 | 9 | 12 | 25 | 3 | 3 | 15 | Yes |
Formulas Used
Compounding and cash‑flow math behind the calculator:
- Periodic rate: r = APR / m, where m is periods per year.
- Future value of principal: FVP = P (1 + r)n.
- Future value of contributions (ordinary annuity): FVC = C · ((1 + r)n − 1) / r.
- Annuity due (start‑of‑period contributions): multiply FVC by (1 + r).
- Tax on interest: each period interest is I = B · r, tax is τI, balance grows by I − τI. This approximates periodic taxation.
- Inflation‑adjusted (real) balance: Real = Nominal / (1 + i)t, where i is inflation rate and t is elapsed years.
Note: When you enable “Contribute at start of period,” contributions are deposited before interest accrues in each period, increasing growth.
How to Use This Calculator
- Enter your Initial balance and a Contribution per period that matches the Compounding frequency.
- Set your Annual interest rate, desired Years, optional Step‑up in contributions, Inflation, and any Tax on interest.
- Choose whether you Contribute at start of period to model an annuity‑due deposit timing.
- Click Calculate. Review the chart and the Results by Year table for nominal versus real balances.
- Export your results to CSV or PDF for records, planning, or sharing.
- Use the Example Scenarios to sanity‑check inputs and compare different saving styles.
FAQs
It is the amount you deposit each compounding period. If frequency is monthly, this is a monthly deposit. If quarterly, it is per quarter, and so on.
A simple periodic tax on interest is applied. Each period the interest earned is reduced by the specified tax rate. Real accounts may tax annually; adjust your rate accordingly.
Nominal is the raw currency amount. Real balance discounts nominal value by inflation, showing purchasing power in today’s terms.
If you deposit at the beginning of each period, enable the option to model an annuity due. This yields slightly higher balances due to an extra period of growth.
Your contribution per period increases once each year by the percentage you specify. This models raises, promotions, or deliberate savings escalations.
Yes. Set the currency symbol field. Formatting uses that symbol and standard numeric separators without converting between currencies.