Amortization Calculator
Generate a full amortization schedule with optional extra payments
What is the Amortization Calculator?
An amortization calculator breaks down your loan payments into exactly how much goes toward interest versus how much actually reduces what you owe. Most people are surprised to find out that for the first several years of a 30-year mortgage, the majority of each payment is interest, not principal. If you have a home loan, car loan, or any fixed installment debt, this tool shows you a full payment schedule, month by month, so you know exactly where your money goes. CalciHub's version also lets you see how much total interest you'll pay over the life of the loan, which is often a number worth knowing.
How Does It Work?
Each monthly payment is calculated so the loan is fully paid off by the end of the term. The standard formula is:
M = P × [r(1 + r)ⁿ] / [(1 + r)ⁿ − 1]
M = Fixed monthly payment
P = Principal loan amount
r = Monthly interest rate (annual rate ÷ 12)
n = Total number of monthly payments (loan term in years × 12)
How to Use CalciHub's Amortization Calculator
1. Enter the loan amount (the total you borrowed, not the purchase price).
2. Input the annual interest rate.
3. Set the loan term in years.
4. Click Calculate to see your monthly payment, total interest paid, and full amortization schedule.
Tip: Scroll through the payment table to find the crossover point, the month when your principal payment finally exceeds your interest payment. For a 30-year mortgage, that point often doesn't arrive until year 18 or 19.
A Quick Example
John bought a home in Austin and took out a $320,000 mortgage at a 6.5% annual interest rate with a 30-year term.
Loan amount: $320,000
Interest rate: 6.5%
Loan term: 30 years
Monthly payment: $2,023
Total paid over 30 years: $728,280
Total interest paid: $408,280
That's more than the original loan amount paid in interest alone. Knowing this, John decided to add $200 to each monthly payment, which cuts about 5 years off the loan and saves roughly $68,000 in interest.
Frequently Asked Questions
It's a full table of every payment you'll make over the life of the loan. Each row shows the payment number, the interest portion, the principal portion, and the remaining balance after that payment. It's the most transparent view of how a loan actually works.
Interest is calculated on your remaining balance. At the start, your balance is highest, so the interest charge is highest. As you pay down the principal each month, the interest portion gradually shrinks and the principal portion grows. This is how amortization works by design.
Significantly. Any extra money you pay goes entirely toward reducing the principal, which means less balance for interest to accrue on in future months. Even $100 extra per month on a 30-year mortgage can cut years off the loan and save tens of thousands in interest.
Yes. The calculator works for any fixed-rate instalment loan — mortgage, auto, personal, or student loan. Just plug in the correct loan amount, interest rate, and term.
Yes, it's completely free. You can run as many loan scenarios as you like without creating an account or entering any personal information.
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