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Time Value of Money Calculator

Solve for any TVM variable - present value, future value, payment, rate, or periods - with annuity due and ordinary annuity modes.

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.

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.

How the result is produced

1

The five-variable equation

All five inputs obey one equation: FV = PV(1+i)^n + PMT x ((1+i)^n - 1) / i, with the payment term multiplied by (1+i) in annuity due mode. Give any four of the five and the fifth is determined - directly for PV, FV, and PMT, by iteration for the rate, the one variable with no closed-form solution.

2

Period and mode consistency

The rate and the period count must be expressed in the payment interval: monthly payments need a monthly rate (annual rate divided by 12) and the term in months. Annuity due moves each payment one period earlier, so for identical inputs its present and future values are the ordinary values multiplied by (1+i).

Good uses

  • Work out the monthly payment on a mortgage or car loan from the amount borrowed, the quoted rate, and the term.
  • Find the regular deposit needed to reach a savings target by a deadline, or how many months of a budgeted payment it takes to get there.
  • Discount a promised future amount - a payout, an inheritance, a settlement - to today's value so it can be compared with cash offers in hand.

Limits and checks

  • Rate units trip up most users: entering 6 for a monthly schedule means 6% per month, which doubles money in about a year. A 6% annual rate with monthly payments is 0.5% per period - divide the annual rate by the number of periods per year first.
  • Mode timing: an ordinary annuity pays at the end of each period, an annuity due at the start. Rent-style contracts are usually due; loan repayments and savings deposits are usually ordinary. The wrong mode changes present and future values by a factor of (1 + i).
  • Quoted rates are ambiguous: '6% annual' usually means 6% nominal compounded monthly, whose effective annual rate is (1.005)^12 - 1, about 6.17%. If the instrument actually compounds yearly, the correct per-period rate is different - confirm what the quote means before relying on the answer.

Common questions

Why does switching from ordinary to annuity due barely change my payment?

Each payment arrives one period earlier, so the payment needed for the same present or future value divides by (1 + i). At 0.5% per month that is roughly 0.5%: the $1,199.10 payment on a $200,000, 30-year, 6% loan becomes about $1,193.13. The gap scales with the rate, so it matters most on high-rate, short-term contracts.

Can it handle a balloon payment or skipped payments?

A balloon fits: enter the balloon amount as the future value alongside the level payment. Payments that vary from period to period cannot be represented in one calculation - the five-variable model assumes a single payment repeated every period. Split the schedule into separate segments, each with its own rate and balance.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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