The Mortgage Amortization Calculator builds the complete period-by-period schedule behind a mortgage, showing principal, interest, escrow and remaining balance for every single payment from the first month to the last. Enter the loan amount, rate, term, tax, insurance, HOA and down payment percentage, and the calculator returns the full table along with total interest paid over the entire life of the loan.
A mortgage's monthly payment number tells only part of the story. Over a 30-year term, hundreds of individual payments each split differently between interest and principal, and the total interest paid across all of them can rival or exceed the original loan amount. This calculator makes that entire trajectory visible rather than leaving it hidden behind one static payment figure.
*These results are estimates for information only, not lending advice.*
See the full schedule from first payment to last
Each row of the schedule shows a payment split into interest, calculated as the remaining balance times the periodic rate, and principal, whatever remains of the fixed principal-and-interest payment after that interest is covered.
Take a $300,000 loan at a 6.5% annual rate over 30 years (360 monthly payments), with $3,600 in annual property tax, $1,200 in annual insurance, no HOA and a 20% down payment.
The principal-and-interest payment is approximately $1,896.20 per month. In month one, interest on the full $300,000 balance at the 6.5%/12 monthly rate comes to $1,625.00, leaving only about $271.20 of that first payment to reduce principal.
The Mortgage Amortization Calculator lists this same breakdown for every one of the 360 months in this example, showing exactly how the interest-to-principal ratio shifts as the balance declines over three decades.
Watch total interest accumulate across three decades
Summing interest across the entire 360-month schedule for this example produces a total interest figure of approximately $382,636.71, more than the original $300,000 borrowed.
This is one of the most important, and most easily overlooked, facts about a 30-year mortgage: over the full term, total interest paid can exceed the original loan amount entirely, a reality that a single monthly payment figure does not make obvious on its own.
Seeing this total interest figure alongside the full schedule, rather than as an isolated statistic, makes clear how much of that cost accumulates specifically in the loan's early years, when the balance, and therefore the interest charged against it, is largest.
Understand how escrow appears alongside the loan schedule
Property tax, insurance and PMI, where they apply, are calculated separately from the principal-and-interest amortization itself and added on top as an escrow component of the total monthly payment. In this example, tax adds $300.00 per month and insurance adds $100.00 per month, with no PMI since the 20% down payment clears the threshold where PMI would otherwise apply.
The core amortization schedule, showing interest and principal against the declining loan balance, proceeds independently of these escrow figures, which stay flat unless tax or insurance costs change over time.
Use the schedule to see the balance at any point in time
Because the schedule tracks the remaining loan balance after every single payment, it answers a question a payment amount alone cannot: how much would be owed if the loan were paid off, refinanced, or sold at any specific point during its term.
Checking the remaining balance at, say, the 10-year or 15-year mark of this 30-year schedule shows how slowly a mortgage balance actually declines in its early years compared to how quickly it declines near the end, a pattern directly caused by the heavy early-year interest weighting.
Know what this schedule assumes
This schedule assumes the interest rate, property tax and insurance figures all stay constant for the full term, with no missed payments, no extra principal payments, and no refinancing along the way. Real mortgages may see tax reassessments, insurance premium changes, or an adjustable rate that would shift the actual schedule from this fixed-rate projection.
Use the Mortgage Amortization Calculator to understand exactly how a 30-year (or any term) mortgage pays down over time and how much total interest accumulates across the full life of the loan.
Frequently asked questions
What does a mortgage amortization schedule show?
A mortgage amortization schedule shows, for every payment over the loan's term, how much goes to interest, how much goes to principal, and what the remaining balance is afterward, tracking the loan from its original amount down to exactly zero at the final payment.
How much total interest is paid on a $300,000, 6.5%, 30-year mortgage?
A $300,000 mortgage at a 6.5% annual rate over a 30-year term accumulates approximately $382,636.71 in total interest across all 360 payments, more than the original loan amount itself.
How much of the first mortgage payment goes to interest versus principal?
On the $300,000, 6.5%, 30-year example, the first monthly principal-and-interest payment of approximately $1,896.20 includes about $1,625.00 in interest and only about $271.20 in principal, since the full loan balance is still outstanding at that point.
Does the amortization schedule include escrow for tax and insurance?
The core amortization schedule tracks principal and interest against the declining loan balance; property tax, insurance and PMI are calculated separately and added to the total monthly payment, staying flat in this projection unless those costs change over time.
Why does the interest-to-principal ratio change over the loan's life?
The interest-to-principal ratio changes because interest is calculated on the remaining balance, which is largest at the start of the loan and shrinks with every payment. As the balance falls, interest shrinks and more of each fixed payment goes toward principal instead.
Summary
The Mortgage Amortization Calculator builds the complete period-by-period schedule for a mortgage, showing interest, principal and remaining balance for every payment.
A $300,000 loan at 6.5% over 30 years pays about $1,896.20 per month in principal and interest, starting with roughly $1,625.00 in interest and $271.20 in principal in month one, and accumulates approximately $382,636.71 in total interest across the full 360-month term, more than the original loan amount.
Figures shown are estimates, not lending advice.