Tested tool guide
Tested browser tools
Checked August 16, 2026
What Time Value of Money Calculator does, with a checked example
Enter any four of the five standard TVM variables - present value, future value, payment, rate, or periods - and the tool solves for the missing one, in ordinary annuity mode (payments at period end) or annuity due mode (payments at period start). The mistake behind most wrong answers: the rate must match the payment interval, so 6% annual with monthly payments means 0.5% per period, not 6. Toggling annuity due shifts every payment one period earlier, so present and future values scale by a factor of (1 + i). Everything is computed in your browser; the amounts you enter never leave the page.
Worked example
A concrete input and expected output from the current implementation.
Input
Loan of $200,000 at 6% annual interest, 30-year term, equal monthly payments at the end of each month, future value 0. Solve for the payment.
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Expected output
$1,199.10 per month.
The term is 360 monthly periods and the monthly rate is 6% / 12 = 0.5%, so the payment is $200,000 x 0.005 / (1 - 1.005^-360) = $1,199.10 - the standard 30-year mortgage figure of $5.9955 per $1,000 borrowed.