What is an amortization schedule?

An amortization schedule is a complete table of periodic loan payments that shows how much of each payment covers the interest charge and how much reduces the outstanding principal balance. Early payments are mostly interest; later payments are mostly principal.

How is the monthly payment calculated?

The fixed monthly payment uses the standard annuity formula: P × r / (1 − (1 + r)^−n), where P is the principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments. For zero-interest loans the payment is simply P ÷ n.

Why does so much of my early payment go to interest?

Interest is charged on the outstanding balance each period. At the start of the loan the balance is highest, so the interest portion is largest. As you pay down the principal over time the interest charge shrinks and more of your fixed payment goes toward principal — this is the nature of amortization.

Does this calculator handle extra principal payments?

The standard schedule assumes the minimum fixed payment every month. If you make extra principal payments your actual balance will drop faster than shown, reducing total interest and shortening the term. For example, an extra $100 a month on a $200,000 loan at 6.5% for 30 years pays it off in 293 months instead of 360 and saves about $55,946 in interest.

Can I use this for a mortgage, auto loan, or personal loan?

Yes. The amortization formula is identical for any fully amortizing installment loan regardless of purpose. Simply enter the correct principal, rate, and term for your loan type.

What does total interest paid mean?

Total interest paid is the sum of every interest charge across all payments — it represents the true cost of borrowing beyond the principal. A longer term lowers the monthly payment but increases total interest paid significantly.

How does a 15-year loan compare with a 30-year loan?

A shorter term raises the payment but cuts total interest sharply. At 6.5% on $200,000, a 15-year loan costs $1,742.21 a month and $113,598.65 in interest, while a 30-year loan costs $1,264.14 a month and $255,088.98 in interest. Set the term in years or months to compare any two terms.

When does more of my payment go to principal than interest?

It depends on the rate and term. On a $200,000 loan at 6.5% for 30 years, principal first beats interest at payment 233, about 19 years in. At lower rates or shorter terms the crossover comes much earlier. The schedule shows the split for every payment, so you can find the exact month for your loan.

Amortization Calculator

Enter your loan amount, interest rate, and term to get the monthly payment and a full amortization schedule showing principal and interest breakdown for every payment.

An amortization calculator splits each fixed loan payment into interest and principal.

Loan Details

Loan Amount

Annual Interest Rate

Loan Term

First Payment Date (optional)

Enter loan details on the left and click Calculate to see your amortization schedule.

Monthly Payment

—

Total Interest

—

Total Cost

—

Payoff Date

—

Principal vs. Total Interest

Principal: — Interest: —

Full Amortization Schedule

#	Date	Payment	Principal	Interest	Balance

Quick answer

An amortization calculator splits each fixed loan payment into interest and principal. The payment is M = P × r(1 + r)^n ÷ ((1 + r)^n − 1), where r is the annual rate ÷ 12 and n is the number of months. Each month the interest is the balance × r, and the rest of the payment lowers the balance. A $200,000 loan at 6.5% for 30 years costs $1,264.14 a month and $255,088.98 in total interest.

Examples

Payment # (of 360)	Principal	Interest
1	$180.80	$1,083.33
12	$191.87	$1,072.26
60	$248.67	$1,015.47
120	$343.87	$920.27
240	$657.53	$606.60
360	$1,257.33	$6.81

Enter the loan amount, rate and term, then click Calculate.

Summary

This amortization calculator computes the fixed monthly payment for any installment loan and generates a complete payment-by-payment schedule. Enter the loan principal, annual interest rate, and loan term in years (or months) to see exactly how much of each payment goes toward principal versus interest, the remaining balance after every payment, and the total cost of the loan.

How it works

Enter the loan principal — the total amount borrowed.
Enter the annual interest rate as a percentage.
Select the loan term in years or switch to months for short-term loans.
Optionally enter a start date to see projected payoff dates in the schedule.
Click Calculate to see the monthly payment, total interest, and full schedule.
Scroll through the amortization table or click Print to get a printable version.

Use cases

Calculating monthly mortgage payments before applying for a home loan.
Comparing total interest costs across different loan terms or rates.
Seeing how much of each early payment goes to interest instead of principal.
Planning an auto loan budget by seeing the exact monthly obligation.
Reviewing a student loan repayment schedule before accepting the terms.
Verifying a lender's amortization table matches your expected payment.
Estimating payoff dates for a personal or business installment loan.
Evaluating refinancing options by comparing interest totals side by side.

Frequently Asked Questions

Last updated: 2026-05-23 · Reviewed by Nham Vu