Finance Calculator

Solve any one of the five time-value-of-money variables (present value, future value, payment, rate, or number of periods) from the other four. Calculates in your browser.

Sign convention: money you receive is positive, money you pay out is negative.

Payment (PMT)

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Present value-
Payment-
Future value-
Rate per period-
Number of periods-
Total of payments-
Total interest-

Show the math

All five variables are linked by one time-value-of-money equation:

PV(1 + i)n + PMT · ((1 + i)n − 1) / i + FV = 0

Here i is the rate per period and n is the number of periods. The equation is rearranged to isolate the variable you are solving for; the rate and number of periods are found numerically. Cash you receive is positive and cash you pay out is negative, a loan has a positive PV and negative payments. All math runs locally in your browser.

What this does

A finance calculator solves the time value of money (TVM): given any four of present value, future value, payment, interest rate, and number of periods, it finds the fifth. It works for loans, savings, and annuities.

How to use it

  1. Choose which variable to solve for.
  2. Enter the other four values.
  3. Use the sign convention: money received is positive, money paid out is negative.
  4. Read the solved value and the totals.

How it works

All five variables satisfy one equation, where i is the rate per period and n is the number of periods. The calculator rearranges it to isolate the one you are solving for; the rate and number of periods are found numerically.

PV(1 + i)ⁿ + PMT · ((1 + i)ⁿ − 1) / i + FV = 0

Understanding your result

The sign convention is what trips people up: cash you receive is positive and cash you pay is negative, so a loan has a positive present value and negative payments, while savings have negative deposits and a positive future value. The interest figure is the difference between everything paid in and everything taken out.

Example

A $20,000 loan at 0.5% per month over 60 months has a payment of about −$386.66, so you repay roughly $23,200, about $3,200 in interest.

Sources & methodology

Last updated .

Frequently asked questions

What is the time value of money?

It is the idea that money available now is worth more than the same amount later because it can earn interest. The five TVM variables (present value, future value, payment, rate, and periods) are linked by one equation.

Why are some numbers negative?

It uses the standard cash-flow sign convention: money you receive is positive, money you pay out is negative. A loan you take has a positive present value and negative payments; savings have negative deposits and a positive future value.

What rate and period should I enter?

Use the rate and count for one period. For a monthly loan, enter the monthly rate (annual ÷ 12) and the number of months.

Is this financial advice?

No. It is a math tool for planning and comparison. Everything is calculated locally in your browser and nothing is saved.