Mortgage Amortization Calculator Guide (2026)
This guide explains mortgage amortization in plain language, shows what an amortization schedule includes, and helps you use the tool correctly. For instant results, use the calculator first.
- Amortization is the process of paying a loan down over time using scheduled payments.
- An amortization schedule shows each payment’s split between principal and interest.
- Early payments are typically interest-heavy, later payments shift toward principal.
- Adding extra payments can reduce total interest and shorten payoff time.
- This guide focuses on principal + interest. Taxes, insurance, and HOA are separate.
What is mortgage amortization?
Mortgage amortization is the structured repayment of a home loan over a fixed term. Each payment reduces your balance while also covering interest, which is the cost of borrowing.
In most standard mortgages, the monthly payment stays consistent for principal + interest, but the split changes over time. That changing split is what your amortization schedule reveals.
What is an amortization schedule?
An amortization schedule is a payment timeline that lists how much of each payment goes to principal and how much goes to interest, along with your remaining balance after each payment.
| Row | What you see | What it means |
|---|---|---|
| Payment | Total monthly payment | Amount paid for that period (principal + interest) |
| Principal | Principal portion | The part that reduces your loan balance |
| Interest | Interest portion | The cost of borrowing for that period |
| Balance | Remaining balance | What you still owe after the payment |
Why early payments feel “slow”
Many people expect their balance to drop quickly at the start. But interest is calculated on your current balance, so in the early months, interest charges are higher.
Over time, as the balance decreases, interest becomes smaller, and more of your payment goes toward principal.
How to use the mortgage amortization calculator
Step 1: Enter your loan amount
Enter the mortgage principal, which is the amount borrowed (not including your down payment if you are starting from the financed amount).
Step 2: Add your interest rate (APR)
Use the annual interest rate shown in your mortgage documents. The calculator converts APR into a monthly rate automatically.
Step 3: Set the loan term
Common terms are 15 or 30 years. A longer term typically lowers the monthly payment but increases total interest.
Step 4: Choose a start date
The start date helps estimate your payoff date. If you’re already paying, you can set it close to your loan’s first payment date.
Step 5: Add extra payments (optional)
Extra monthly payments reduce principal faster, which can shorten the loan and reduce total interest.
Common mistakes to avoid
- Mixing purchase price and loan amount: amortization uses the financed balance, not the home price.
- Expecting taxes and insurance here: this is principal + interest only.
- Using a rounded rate incorrectly: small rate differences can change interest totals.
- Ignoring extra payments: even small extra payments can materially change payoff time.
Mortgage amortization vs mortgage payment
Amortization focuses on how the loan balance reduces over time. Mortgage payment calculators often include additional costs like property taxes, homeowners insurance, HOA, and PMI (if applicable).
If your goal is monthly budgeting, use the Mortgage Payment Calculator. If your goal is payoff planning and understanding interest over time, amortization is the right tool.