calculate-loan

01 Loan payments

Estimated Car Loan Payment Calculator and Formula

Calculator No. 01-6860 · Updated · Formula and assumptions shown below

Monthly payment $405.53
Total interest
$4,331.67
= Monthly payment × loan term × 12 − loan amount
Loan amount
$20,000
Input
Interest rate (APR)
8 %
Input
You enter
Loan amount ($), Interest rate (APR) (%), Loan term (years)
You get
Monthly payment ($), Total interest ($)
Rounding
2 dp

Estimate for education, not financial advice. The result follows from the numbers you enter and the formula shown. It is not a quote or an offer, and it does not include fees, taxes or insurance unless the calculator asks for them. Ask your lender for the exact figures.

This estimated car loan payment calculator works out a fixed monthly payment from the amount borrowed, annual percentage rate (APR), and loan term. Enter those three figures to see the estimated payment and total interest over the term; the estimate excludes taxes, fees, and other costs unless they are included in the loan amount.

Formula

The calculator uses the standard amortizing-loan payment formula:

Monthly payment = P × r ÷ [1 − (1 + r)−n]

  • P is the amount borrowed, in dollars.
  • r is the monthly interest rate as a decimal: APR ÷ 100 ÷ 12, or APR ÷ 1200.
  • n is the number of monthly payments: loan term in years × 12.

The calculator displays the payment to the nearest cent. Total interest is calculated as the displayed monthly payment multiplied by the number of payments, minus the original principal: interest = monthly payment × n − P. Because the payment is rounded to cents, this total is an estimate and may differ slightly from a lender’s schedule, especially if the final payment is adjusted.

Worked Example

Using the calculator’s default values—$20,000 borrowed, 8% APR, and a five-year term—the monthly rate is 8 ÷ 1200 = 0.0066667, and the number of payments is 5 × 12 = 60.

Substitute those values into the payment formula:

$20,000 × 0.0066667 ÷ [1 − (1.0066667)−60] ≈ $405.53

The estimated total of the 60 rounded payments is $405.53 × 60 = $24,331.80. Subtracting the $20,000 principal gives estimated total interest of $24,331.80 − $20,000 = $4,331.80. The calculator’s results are therefore a $405.53 monthly payment and $4,331.80 in total interest.

Assumptions

  • The interest rate stays fixed for the full term.
  • Payments are equal, made monthly, and paid at the end of each monthly period.
  • Interest is compounded monthly using the APR divided by 12.
  • The calculation excludes separate fees, taxes, insurance, and add-ons. It also does not calculate a down payment or trade-in value; subtract those from the vehicle’s financed amount before entering the loan amount if they affect how much is borrowed.

When to Use an Estimated Car Payment

Use this calculation to understand how the amount financed, APR, and term affect a fixed-payment loan. It can help you compare hypothetical combinations on the same assumptions or check a quoted payment. It is arithmetic for education, not financial advice, and it does not establish what a person can afford or whether a lender will approve an application.

For a useful estimate, enter the amount you expect to borrow rather than the vehicle’s advertised price alone. The amount financed can differ from the price after a down payment, trade-in credit, taxes, registration costs, dealer or lender charges, and optional products are accounted for. Those amounts vary by transaction, so get the actual figures from the seller and lender rather than assuming the calculator includes them.

How to Read the Results

The monthly payment is the regular principal-and-interest payment implied by the inputs. In a standard amortizing loan, each payment covers interest due for that period and reduces some principal. Early payments generally devote a larger share to interest because the outstanding balance is higher; later payments devote a larger share to principal. The total interest figure estimates the interest paid across all scheduled payments, not the total cost of owning the vehicle.

A longer term spreads repayment over more months and generally lowers the formula’s monthly payment for the same principal and rate, while increasing the number of periods over which interest accrues. A higher APR raises the payment and total interest when other inputs remain unchanged. A larger down payment can reduce the amount financed, but the calculator models that only when you enter the smaller principal.

Common Inputs and Calculation Limits

  • APR: Enter a yearly percentage, such as 8 for 8%, not 0.08 or a monthly rate. Use the APR supplied for the specific quote; do not treat the default as a current market rate.
  • Loan amount: Enter dollars actually financed. If you include a fee or optional item in the amount, the estimate treats it as part of principal and accrues interest on it.
  • Term: The input is in years, and the formula converts it to months. The calculator supports terms from 0.0833 through 50 years, but an unusual input range is not evidence that a lender offers that term.
  • Rounding: Results are shown to cents, but a lender’s payment schedule may use different conventions or adjust its final installment. Do not infer an exact payoff balance from the rounded estimate.

This formula assumes a fixed rate and regular monthly payments. It does not model a variable rate, irregular payment dates, a balloon payment, deferred payments, payment holidays, or a changing balance due to extra payments. APR conventions and the treatment of charges can also differ from the simple monthly-rate approximation used here. Ask the lender for the payment schedule and the precise amount financed when reviewing a real offer.

Frequently Asked Questions

How do I estimate a car loan payment?
Enter the amount financed, the quoted APR as a yearly percentage, and the term in years. The calculator converts the APR to a monthly rate and the term to a number of monthly payments, then applies the fixed-payment formula.

Does the estimate include taxes and fees?
No. It includes only the principal entered and interest calculated from the APR and term. If a cost is financed, include it in the loan amount; otherwise, the result will not reflect it.

Is APR the same as the monthly interest rate?
No. APR is entered as a yearly percentage. This calculator approximates the monthly rate by dividing APR by 12, so an 8% APR becomes 0.0066667 per month as a decimal.

Why might a lender’s payment differ from the calculator?
The lender may use a different amount financed, include financed charges, use different timing or calculation conventions, or adjust the final payment. Compare the same principal, rate, term, and included charges, and request the lender’s written payment schedule.

Does a longer term always mean lower total cost?
No. For the same principal and APR, extending the term usually reduces the scheduled monthly payment but increases the number of payments and generally the total interest under this formula. The calculator does not evaluate whether a term is suitable for an individual.

The result is an estimate, and the lender’s disclosure gives the exact figures.

Related

Formula used
in p | Loan amount | $ | 20000 | 1 | 100000000
in apr | Interest rate (APR) | % | 8 | 0.01 | 100
in yrs | Loan term | years | 5 | 0.0833 | 50
out pmt | Monthly payment | $ | p * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)) | 2
out int | Total interest | $ | pmt * yrs * 12 - p | 2

Each line is one input (in, sel, list) or one result (out: label, unit, formula, decimals). How the calculators work

Method: the standard loan formula for this calculation, fixed rate and monthly compounding unless stated, rounded as each result states. Not financial advice; no lender, rate or product is recommended. See formulas and assumptions, the disclaimer or report an error.

More in this section

The whole Loan payments section →