N
10.00
TVM Calculator
Solve for any single Time Value of Money variable given the other four.
Future Value
$17,908.48
Rate
6.00%
PV
-$10,000.00
PMT
$0.00
FV
$0.00
Convention follows standard financial calculators: cash outflows are negative, inflows positive.
How to use the TVM Calculator
The TVM Calculator is free and runs entirely in your browser — no sign-up, and nothing you enter leaves your device. It opens pre-filled with a realistic example, so you can see how it works before replacing any figure with your own; the results update as you type. Press Calculate to refresh the result panel, or Reset to return to the example.
The inputs it asks for:
- Solve For — choose from 5 options (Future Value, Present Value, Payment, …).
- Number of Periods (N) — a number.
- Interest Rate per Period — a percentage (enter 6 for 6%).
- Present Value — a dollar amount.
- Payment per Period — a dollar amount.
- Future Value — a dollar amount.
- Payment Timing — choose one — End of Period, Beginning of Period.
The formula
The calculator holds four of the five time-value-of-money variables fixed and solves for the fifth, using the single equation that ties a present sum, a stream of level payments and a future sum together at one rate:
PV·(1 + r)ⁿ + PMT·((1 + r)ⁿ − 1)/r·(1 + r·type) + FV = 0- N
- the number of periods
- r
- the interest rate per period
- PV / FV
- the present value (today) and future value (at the end)
- PMT
- the level payment made each period
- type
- 0 if payments fall at period-end, 1 if at the start
There is no closed form for the rate, so it is found numerically (bisection between −99% and 500%). The sign convention matters: money you pay out is negative, money you receive is positive — mixing the signs is the usual reason "solve for rate" returns no answer.
Worked example
Using the example values — Solve For Future Value, Number of Periods (N) 10, Interest Rate per Period 6%, Present Value -$10,000.00, Payment per Period $0.00, Future Value $0.00, and 1 more — the TVM Calculator returns a Future Value of $17,908.48. It also reports N (10.00), Rate (6.00%), PV (-$10,000.00).
Prefer your own numbers? Change any field above and this recomputes instantly.
Key terms
- Present value
- What a future amount is worth today, discounted at a given rate.
- Future value
- What a present amount, plus any payments, grows to by the end.
- Period
- The unit the rate and the count share — the rate must match the periods (a 6% annual rate is 0.5% a month).
- Annuity due
- Payments made at the start of each period rather than the end.
Frequently asked questions
What's the sign convention?
Outflows are negative, inflows positive — e.g. deposit PV as −1,000 and expect FV 2,000. Getting the signs wrong is what makes a "solve for rate" fail with no answer.
Do the rate and N have to use the same units?
Yes. If N is in months, the rate must be the monthly rate (annual ÷ 12). Pairing 6% with 360 months treats 6% as a monthly rate.
What does payment timing change?
Beginning-of-period (annuity due) payments each earn one extra period of interest, so they produce a higher future value and require a smaller payment than end-of-period.