How to Use the Future Value Calculator
Complete the controls in order, then review the projection in the result section.
- Enter Present value ($) and Contribution per period ($). Both can be 0, but at least one must be greater than 0.
- Choose Contribution timing: Beginning of each period or End of each period.
- Enter Annual interest rate (%) and Term, then choose Term unit: Years or Months.
- Choose Compounding / contribution frequency.
- Click Calculate to generate the result.
- Click Reset to clear the inputs, errors, and result section.
What the Result Shows
The result shows Future value, Total money in (present value + contributions), and Total interest / growth earned. The assumptions table includes the periodic rate, total periods, growth of the present value, growth of contributions, and total contributions.
The page also displays the formula and assumptions used, followed by a schedule with the period, contribution, interest earned, and balance. When the total exceeds 600 periods, the schedule shows the first 600; the calculation itself allows up to 4,800 periods.
Formula and Timing Conventions
The calculator combines growth of the starting amount with growth of the contribution stream:
FV = PV x (1 + i)^N + PMT x [((1 + i)^N - 1) / i] x (1 + i x d)
- PV is the present value; PMT is the contribution per period.
- i is the annual interest rate divided by periods per year; N is the total number of periods.
- d is 1 for Beginning of each period and 0 for End of each period.
- At a zero periodic rate, the contribution calculation uses
PMT x N. - The selected frequency controls both compounding and contributions. Options are annually (1/year), semi-annually (2/year), quarterly (4/year), monthly (12/year), bi-weekly (26/year), weekly (52/year), and daily (365/year).
- Beginning of each period contributions earn one extra period of interest compared with End of each period contributions.
Validation and Calculation Limits
Present value ($) and Contribution per period ($) must be 0 or greater, with at least one greater than 0. Annual interest rate (%) must be from 0 to 100%, and Term must be greater than 0. After rounding, the total number of periods must be above 0 and no more than 4,800. Invalid inputs stop the calculation and show an error message.
Copying and Downloading the Result
Use Copy result to copy the plain-text inputs, formula-related values, totals, and final result. Use Download result (.txt) to save the same plain-text summary. Neither export includes the displayed schedule rows.
If clipboard copying fails, the interface shows Could not copy - select and copy manually. Select the result text and copy it yourself.
Limitations and Local Calculation
The calculation runs locally in your browser using the values you enter. It does not fetch live market rates. It assumes a fixed rate and evenly spaced contributions for the full term, and does not model investment risk, fees, or taxes.
The tool does not support different compounding and contribution frequencies, variable rates, or irregular contribution amounts. It is a mathematical projection, not investment advice.
Frequently Asked Questions
What is the future value formula used by this calculator?
FV = PV x (1 + i)^N + PMT x [((1 + i)^N - 1) / i] x (1 + i x d), where PV is the present value, PMT is the periodic contribution, i is the periodic interest rate (annual rate divided by periods per year), N is the total number of periods, and d is 1 if contributions are made at the start of each period or 0 if made at the end.
What is the difference between contributions at the beginning vs. end of a period?
If contributions are made at the beginning of each period (an annuity due), each contribution earns interest for one extra period compared to contributions made at the end of each period (an ordinary annuity). This produces a slightly higher future value for beginning-of-period contributions at the same rate and term.
How does compounding frequency affect the result?
This calculator uses the same frequency for compounding and contributions. The annual rate is divided by the number of periods per year to get the periodic rate, and the term is converted to a matching number of periods. More frequent compounding produces a higher future value at the same nominal annual rate.
Does this tool give investment advice?
No. It performs a transparent mathematical projection on the numbers you enter. It does not fetch live market rates, model investment risk or fees, or provide personalized financial or investment advice.