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Loan Payment Calculator

Estimate a fixed monthly principal-and-interest payment from loan amount, annual interest rate, and term. Use it for simple amortized loan scenarios before adding taxes, insurance, fees, or variable-rate assumptions.

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$
%
years

Result

Monthly payment
$1,580.17

Principal and interest payment only.

Total paid
$568,861.22
Total interest
$318,861.22

How loan payment calculation works

The calculator converts the annual interest rate into a monthly rate and converts the loan term from years into monthly payments.

If the rate is zero, payment is simply principal divided by the number of payments. Otherwise, it uses the standard fixed-rate amortization formula.

The result is principal and interest only. It does not include taxes, insurance, origination fees, PMI, HOA dues, late fees, or variable-rate adjustments.

Useful next steps

Loan payment formula

monthlyRate = annualRatePercent / 100 / 12; numberOfPayments = years * 12; payment = P * [r(1+r)^n] / [(1+r)^n - 1]

The formula estimates the fixed monthly payment for an amortizing loan. Total paid is monthly payment multiplied by number of payments, and total interest is total paid minus principal.

  • P is principal.
  • r is the monthly interest rate.
  • n is the number of monthly payments.
  • When r is 0, payment equals principal divided by n.

What the Numbers Mean

Loan amount
The principal borrowed before interest. Include financed fees only if you want them treated as part of the loan amount.
Annual interest rate
The yearly rate used to calculate monthly interest. The calculator does not separately model APR fees.
Loan term
The repayment length in years. Longer terms usually lower payment but increase lifetime interest.
Total interest
The estimated amount paid above principal if all scheduled payments are made as modeled.

Assumptions

  • The loan has a fixed annual interest rate.
  • Payments are monthly and made on schedule.
  • The estimate is principal and interest only.
  • Taxes, insurance, origination fees, escrow, late fees, prepayment penalties, and variable-rate changes are excluded.
  • The calculator summarizes payment, total paid, and total interest, but does not generate a full amortization schedule.

Worked Examples

Thirty-year loan

Input
$250,000 principal, 6.5% annual rate, 30 years
Formula
P = 250,000, r = 0.065 / 12, n = 360
Output
$1,580.17 monthly payment

The formula uses a monthly rate of about 0.5417% across 360 payments.

Zero-rate loan

Input
$12,000 principal, 0% annual rate, 5 years
Formula
$12,000 / 60 payments
Output
$200 monthly payment

With no interest, 12,000 divided by 60 payments equals 200.

Five-year personal loan

Input
$18,000 principal, 9% annual rate, 5 years
Formula
P = 18,000, r = 0.09 / 12, n = 60
Output
$373.65 monthly payment

The loan is paid over 60 monthly payments using the amortization formula.

Common Fixed-Rate Loan Payment Examples

These examples use standard monthly amortization and show principal-and-interest payment only.

ExampleRateTermMonthly paymentTotal interest
$10,000 loan6%3 years$304.22$951.90
$20,000 loan8%5 years$405.53$4,331.67
$25,000 loan11%5 years$543.56$7,613.63
$30,000 loan6.9%5 years$592.62$5,557.29
$250,000 loan6.5%30 years$1,580.17$318,861.22

Taxes, insurance, escrow, origination fees, late fees, and variable-rate changes are not included.

How Rate and Term Change the Payment

The same principal can produce very different monthly payments and total interest depending on the rate and term.

Shorter term

$20,000 loan, 6% annual rate, 3 years

$608.44/month and $1,903.79 interest

The payment is higher, but the loan is repaid faster and total interest is lower.

Longer term

$20,000 loan, 6% annual rate, 5 years

$386.66/month and $3,199.36 interest

The payment is lower, but interest accrues for more months.

Higher rate

$20,000 loan, 10% annual rate, 5 years

$424.94/month and $5,496.45 interest

A higher rate raises both the monthly payment and the lifetime borrowing cost.

Related Guides for Loan Payments

Use these pages when the decision depends on payment mechanics or total interest cost.

Frequently Asked Questions

Does this include taxes and insurance?

No. The payment is principal and interest only. Property taxes, insurance, HOA fees, and other charges are excluded.

Can this handle a zero interest rate?

Yes. If the annual rate is 0, the calculator divides principal by the number of monthly payments.

Is the result an amortization schedule?

No. It estimates the fixed monthly payment, total paid, and total interest, but it does not list each monthly balance.

Why is total interest higher on longer loans?

Longer terms spread payments over more months. Even when the monthly payment is lower, interest has more time to accrue.

Can I use this for a mortgage?

It can estimate principal and interest, but a full mortgage payment may also include property taxes, homeowners insurance, PMI, HOA dues, and escrow changes.

When should this not be used?

Do not use it for adjustable-rate loans, interest-only periods, balloon payments, fees financed into the loan, or irregular payment schedules.

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Disclaimer

This calculator estimates principal and interest only. It does not constitute lending, mortgage, tax, legal, or financial advice.