Mortgage Amortization Calculator
See your monthly mortgage payment and a full year-by-year amortization schedule. Enter the home price, down payment, rate, and term.
| Year | Principal | Interest | Balance |
|---|---|---|---|
| 1 | $3,577 | $20,695 | $316,423 |
| 2 | $3,816 | $20,455 | $312,607 |
| 3 | $4,072 | $20,200 | $308,535 |
| 4 | $4,345 | $19,927 | $304,191 |
| 5 | $4,636 | $19,636 | $299,555 |
| 6 | $4,946 | $19,325 | $294,609 |
| 7 | $5,277 | $18,994 | $289,332 |
| 8 | $5,631 | $18,641 | $283,701 |
| 9 | $6,008 | $18,264 | $277,693 |
| 10 | $6,410 | $17,861 | $271,283 |
| 11 | $6,839 | $17,432 | $264,444 |
| 12 | $7,297 | $16,974 | $257,146 |
| 13 | $7,786 | $16,485 | $249,360 |
| 14 | $8,308 | $15,964 | $241,053 |
| 15 | $8,864 | $15,407 | $232,189 |
| 16 | $9,458 | $14,814 | $222,731 |
| 17 | $10,091 | $14,180 | $212,640 |
| 18 | $10,767 | $13,505 | $201,873 |
| 19 | $11,488 | $12,784 | $190,385 |
| 20 | $12,257 | $12,014 | $178,128 |
| 21 | $13,078 | $11,193 | $165,050 |
| 22 | $13,954 | $10,317 | $151,096 |
| 23 | $14,889 | $9,383 | $136,207 |
| 24 | $15,886 | $8,386 | $120,321 |
| 25 | $16,950 | $7,322 | $103,372 |
| 26 | $18,085 | $6,187 | $85,287 |
| 27 | $19,296 | $4,976 | $65,991 |
| 28 | $20,588 | $3,683 | $45,403 |
| 29 | $21,967 | $2,304 | $23,436 |
| 30 | $23,436 | $833 | $0 |
Principal & interest only. Excludes property tax, homeowners insurance, PMI, and HOA dues.
How to use this calculator
Enter the home price, your down payment (dollar amount or percentage), the annual interest rate, and the loan term in years. You'll see:
- Your loan amount (home price minus down payment)
- Your fixed monthly principal-and-interest payment
- Total interest paid over the full term
- A year-by-year amortization schedule showing annual interest, annual principal, and the remaining balance at year-end
Adjust the term between 15 and 30 years, or change the rate, to compare scenarios side by side. The difference in total interest between a 30-year and a 15-year mortgage on the same home can be substantial.
How mortgage amortization works
A fixed-rate mortgage is designed so that the monthly payment stays constant for the entire term, while the composition of each payment — how much goes to interest versus how much reduces the balance — shifts dramatically over time.
This happens because interest is calculated as a percentage of the remaining balance. At the start of the loan, the balance is at its highest, so a large fraction of each payment covers interest. As you make payments and the balance falls, less interest accrues each month, which means more of the same fixed payment goes to principal. The process accelerates toward the end: in the final years, almost the entire payment goes to paying down what you originally borrowed.
This is also why making extra principal payments early in the mortgage is so effective. Every extra dollar applied to principal in year one reduces the balance on which interest accrues for the remaining 29 years — the savings compound across all future payments.
Worked example — step by step
A $400,000 home with a $80,000 (20%) down payment leaves a loan of $320,000. At 6.5% annual interest over 30 years (360 monthly payments):
- Monthly rate: 6.5% ÷ 12 = 0.5417%
- Monthly payment: $320,000 × [0.005417 × (1.005417)³⁶⁰] ÷ [(1.005417)³⁶⁰ − 1] ≈ $2,023/month
- Total paid over 360 months: $2,023 × 360 = $728,280
- Total interest: $728,280 − $320,000 = $408,280
In year 1, roughly $20,600 goes to interest and only about $3,700 to principal — the balance barely drops, ending near $316,300. By year 20, the balance is around $191,000 and principal makes up a larger share of each payment. In year 30, the final payments are nearly all principal and the loan reaches zero.
Now compare to a 15-year term at the same rate: the payment rises to about $2,790/month, but total interest falls to roughly $142,200 — saving over $265,000 compared to the 30-year option.
How to interpret your amortization schedule
Look at the interest column in the first few years: a large portion of your mortgage payments is cost, not equity-building. This is normal for long-term loans, but it underscores why extra principal payments in the early years are particularly valuable.
The balance column tells you how much you would still owe at any year-end. This is useful if you expect to sell or refinance before the end of the term — you can see exactly what remains to be paid off.
Subtracting the end-of-year balance from your home's market value gives you your approximate loan-based equity. (Market value can rise or fall independently of the loan balance, so your actual equity may be more or less.)
Common mistakes to avoid
- Assuming the payment shown is your total housing cost. This calculator shows principal and interest only. Property taxes, homeowners insurance, PMI, and HOA fees will add to your actual monthly outlay — often by $300–$700 or more per month.
- Comparing only monthly payments when choosing a term. A 30-year mortgage has a lower payment than a 15-year, but the total interest cost can be two or three times higher. Always review the total interest row when comparing terms.
- Thinking you've built significant equity in the first few years. Early in a 30-year mortgage, equity builds very slowly because most of each payment is interest. Don't count on large equity for a quick resale unless home values have appreciated significantly.
- Forgetting that refinancing resets the clock. If you refinance into a new 30-year loan after 10 years, the early-interest effect starts over. Running the numbers on a shorter term for the refinance is often worthwhile.
- Not accounting for how extra payments affect the schedule. Extra principal payments reduce the balance going forward, but the nominal monthly payment stays the same (your lender won't automatically lower it). You either pay off the loan earlier, or you reduce future interest while keeping the same payment.
The formula
Payment = P × [ r(1 + r)n ] ÷ [ (1 + r)n − 1 ]
Where: P = loan amount (home price − down payment), r = monthly interest rate (annual rate ÷ 12), n = total monthly payments (years × 12).
For each period: Interest = remaining balance × r. Principal = Payment − Interest. New balance = old balance − Principal.
How we calculate this
We compute the level monthly principal-and-interest payment with the standard fixed-rate amortization formula: Payment = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1], where P is the loan amount (home price minus down payment), r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments. We then build the year-by-year schedule by applying interest (monthly rate × remaining balance) and subtracting from each payment to find the principal reduction, tracking the declining balance through the final payment. Taxes, insurance, PMI, and HOA are not included.
Sources
Frequently asked questions
What is a mortgage amortization schedule?
It's a complete table showing every monthly payment over the life of your loan, split into the principal and interest portions, with the remaining balance after each payment. Early payments are mostly interest; later ones are mostly principal. The schedule makes it easy to see exactly where your money goes at any point in the loan.
How much of my early payments goes to interest?
On a 30-year mortgage, the first several years are heavily weighted toward interest because interest accrues on a large outstanding balance. In the first year of a $320,000 loan at 6.5%, roughly 80–85% of each payment typically goes to interest rather than reducing what you owe. As the balance shrinks, that ratio gradually reverses.
Does this include taxes and insurance?
No. This schedule shows principal and interest only — the two components that amortize your loan balance. Your actual monthly payment will also include property tax, homeowners insurance, PMI (if applicable), and HOA dues, often bundled as 'PITI.' Use our full Mortgage Calculator for an estimate that includes those items.
How can I pay off my mortgage faster?
Making extra principal payments is the most direct method. Even an additional $100–$200 per month can cut years off a 30-year mortgage and save tens of thousands in interest. Biweekly payments (half the monthly amount every two weeks) effectively add one full payment per year. Refinancing to a shorter term, such as 15 years, is another powerful option if rates are favorable.
What is the equity I build each year?
Your equity increases each month by the principal portion of that payment, plus any appreciation in the home's value. The amortization schedule shows the loan balance at the end of each year; subtracting that from the home's current market value gives your equity. Early in the loan, equity from payments builds slowly because so little goes to principal.
How does refinancing appear in the amortization schedule?
Refinancing resets the amortization clock. If you refinance a 30-year mortgage after 7 years into a new 30-year loan, your new schedule starts fresh — meaning the early years of the new loan are again mostly interest. Shortening the new term (say, to 20 or 15 years) partially offsets this by accelerating principal repayment.
Is a 15-year mortgage worth it over 30 years?
A 15-year mortgage typically carries a lower interest rate and builds equity faster, but the monthly payment is substantially higher than a 30-year. The total interest paid on a 15-year loan is dramatically less — often less than half of a 30-year loan on the same principal. Whether it makes sense depends on your cash flow, other financial goals, and whether the payment is comfortably affordable.
What happens if I make one extra payment per year?
On a 30-year mortgage, making one additional full payment toward principal each year can shorten the loan by several years and save a significant amount in interest — often five or more years on the term. The exact savings depend on your interest rate and when in the loan you start making extra payments.