Amortization Schedule Calculator
See a full month-by-month breakdown of your loan payments — exactly how much goes to interest, how much to principal, and your balance at every step.
*Estimates only. Actual amortization may differ with escrow, fees, or rate changes.
Amortization Table
| # | Payment | Principal | Interest | Balance |
|---|
Showing the first 12 months plus year-end summaries.
📅 Understanding Your Loan Schedule
How amortization actually works, month by month.
How it Works
Each fixed monthly payment is split between interest (charged on the current balance) and principal (which reduces the balance). As the balance shrinks, more of each payment goes toward principal.
The Formula
Payment = P × [r(1+r)^n] / [(1+r)^n − 1], where P is principal, r is the monthly interest rate, and n is the total number of payments. Each month: Interest = Balance × r; Principal = Payment − Interest.
Pro Tip
Making one extra full payment per year (or rounding up your monthly payment) accelerates the principal paydown and can cut years off a 30-year mortgage while saving tens of thousands in interest.
Frequently Asked Questions
What is an amortization schedule? +
An amortization schedule is a table listing every payment over the life of a loan, showing how much of each payment goes toward interest versus principal, and the remaining balance after each payment. It reveals that early payments are mostly interest while later payments are mostly principal.
Why is more of my early payments interest? +
Interest is charged on the outstanding balance each period. Early in the loan, the balance is largest, so the interest portion is largest too. As the balance shrinks with each payment, the interest charged shrinks and a larger share of your fixed payment goes to principal.
Does the monthly payment change over the loan term? +
For a standard fixed-rate, fixed-term loan, no. The total monthly payment stays the same for the entire term; only the split between principal and interest shifts each month. Adjustable-rate loans work differently and can change payment amounts.
How does an extra principal payment affect the schedule? +
Any extra amount applied directly to principal reduces the balance the interest is calculated on for every remaining month, which shortens the loan term and cuts total interest paid. Even small recurring extra payments can shave years off a 30-year mortgage.
What's the difference between amortization and simple interest? +
Simple interest is calculated only on the original principal for the full term. Amortized loans recalculate interest each period on the current outstanding balance, so the interest portion naturally declines as you pay down the loan — which is how most mortgages, auto loans, and personal loans work.
Why does total interest paid vary so much between a 15-year and 30-year mortgage? +
A shorter term means the balance is paid down faster, so less total time accrues interest, even though the monthly payment is higher. A 30-year loan spreads principal repayment out, keeping the balance — and thus the interest charged — higher for much longer, often doubling or tripling total interest paid.