Mortgage Amortization Calculator
Amortization Schedule Table
Complete payment-by-payment amortization table detailing principal reduction, interest charges, and remaining balance.
| Year | Payments | Principal Paid | Interest Paid | Total Paid | Year-End Balance |
|---|
Definitions
How to read a payment schedule table
An amortization table (also called a payment schedule or amortization chart) lists every payment from the first to the last, and breaks each one into two parts: the portion that pays down interest, and the portion that pays down principal. Reading it left to right tells you the story of the loan.
Early payments on an amortized loan are interest-heavy because interest is calculated on the outstanding balance, which is largest at the start. As the balance drops, less interest accrues each month, so more of the fixed payment is freed up to reduce principal — this is the amortization curve you can see in the charts and split bars above.
M = P × [ r(1 + r)ⁿ ] / [ (1 + r)ⁿ − 1 ]
What extra payments really save
Anything you pay above the required amount goes straight to principal, which permanently shrinks the base that all future interest is charged on. The effect compounds, so it’s far larger than the extra money itself.
On the default $350,000 loan at 6.5%:
Two practical cautions: check your loan agreement for prepayment penalties first — they’re rare on mortgages but more common on some auto and personal loans — and tell your servicer in writing that extra money should be applied to principal, not held as a prepaid future installment, which is the default at some lenders.
Loans that don’t amortize the way you expect
Not every loan follows a clean, fully-amortizing schedule. Knowing which kind you have changes how you should read its numbers.
Interest-only loans
Charge only the interest for an initial period, so the balance doesn’t move at all until the full amortizing payment kicks in later.
Balloon loans
Amortized over a longer schedule than their actual term, leaving a large lump sum due at the end — use the balloon field above to model one.
Negative amortization
Happens when the payment is smaller than the interest due; the shortfall is added to the balance and the debt grows even though payments are being made.
Adjustable-rate loans (ARMs)
Re-cut the schedule at every rate reset, so any amortization schedule you build for an ARM is only accurate until the next adjustment.
Credit cards
Have no fixed end date — the minimum payment is a percentage of the balance, so it falls as the balance falls and payoff stretches out.
Reamortized loans
After a lump-sum payment, rate change, or recast, the remaining balance is spread across the remaining term at a new, recalculated payment.
One calculator, every kind of amortized loan
Switch the loan type above and the calculator adjusts its defaults. Under the hood, every one of these is the same amortization math — only the typical rate, term, and extra fields change.
Mortgage amortization calculator
Model a home loan amortization schedule over 15, 20, or 30 years, and see how extra principal payments shorten a mortgage.
Car loan amortization calculator
Auto loan terms are shorter and rates behave differently — see the full payment schedule for a new or used car loan.
Personal loan amortization calculator
Fixed-rate personal loans amortize the same way as a mortgage, just on a shorter, unsecured schedule.
HELOC amortization calculator
Model the repayment phase of a home equity line of credit once it converts from interest-only to fully amortizing.
Credit card amortization calculator
See how a fixed payoff plan would amortize a credit card balance if you stopped charging and paid a flat amount monthly.
Bank loan calculator
Any fixed-rate installment loan from a bank or credit union follows the same amortized-loan calculation shown here.
This tool covers the same ground as a bank’s loan calculator, Bankrate’s amortization calculator, calculator.net’s mortgage calculator, Zillow’s mortgage calculator, or the classic Bret Whissel amortization calculator formula — enter principal, rate, and term to get a monthly payment amount, a balance chart, an annual summary, and a full, downloadable amortization table, free and without an account.
Standard Amortization Benchmark Matrix
| Loan Principal | Interest Rate | 15-Year Monthly Payment | 15-Year Total Interest | 30-Year Monthly Payment | 30-Year Total Interest |
|---|---|---|---|---|---|
| $150,000 | 6.50% | $1,306 | $85,066 | $948 | $191,332 |
| $250,000 | 6.50% | $2,176 | $141,777 | $1,580 | $318,887 |
| $350,000 | 6.50% | $3,047 | $198,488 | $2,212 | $446,441 |
| $500,000 | 6.50% | $4,353 | $283,554 | $3,160 | $637,773 |
Amortization, explained
What is amortization?
Amortization is paying off a loan through fixed, scheduled payments, with each one split between interest and principal until the balance reaches zero.
The word is spelled “amortisation” in British and Commonwealth English, and the loan itself is described as “amortized.”
What is an amortization schedule?
An amortization schedule is a table listing every payment over the life of a loan, splitting each one into interest and principal and showing the remaining balance afterward.
It’s also called an amortization table — the two terms are used interchangeably, and this calculator produces one automatically, both as a full monthly table and grouped into an annual summary.
How is my monthly payment calculated?
Your payment depends on three numbers: the amount borrowed, the interest rate, and the number of payments, using the formula M = P × (r(1+r)ⁿ) / ((1+r)ⁿ − 1).
P is the principal, r is the periodic (monthly) interest rate, and n is the total number of payments. This calculator applies it instantly and shows the result along with the full payment breakdown.
Why is so much of my early payment interest?
Because interest is charged on what you currently owe, and at the start you owe the entire amount.
On a $350,000 loan at 6.5%, the first month’s interest alone is $1,895.83 out of a $2,212.24 payment. The proportion improves every month, but on a 30-year term it takes nearly 20 years before more of your payment goes to principal than to interest.
Can I pay my loan off faster?
Yes — any amount you pay on top of the required payment goes straight to the principal, which shrinks the base on which future interest is charged.
On the default loan, an extra $100 a month cuts about three and a half years off the term and saves roughly $62,600 in interest. Check your loan agreement for prepayment penalties before committing.
Do biweekly payments really pay off a loan faster?
Yes, but not for the reason most people assume.
Paying half your monthly payment every two weeks produces 26 half-payments a year, which is 13 full payments rather than 12. The saving comes from that one extra payment a year, not from the payment frequency itself.
What is negative amortization?
Negative amortization occurs when your payment is smaller than the interest owed for that period.
The unpaid interest is added to the balance, so the debt grows despite the payments. It can appear in some adjustable-rate mortgages with payment caps, in graduated-payment plans, and in income-driven student loan repayment.
Does my amortization schedule change if the interest rate changes?
On a fixed-rate loan, no — the rate and payment are locked for the whole term.
On an adjustable-rate loan, the schedule is recalculated at every reset using the new rate and the remaining balance and term, producing a new fixed payment until the next adjustment.
Can this calculator handle extra payments or a balloon payment?
Yes — open ‘TAXES, INS, HOA & PMI, EXTRA’ above to add a recurring extra monthly amount or a lump-sum balloon payment due at the end of the term.
Can I calculate a schedule from a fixed payment instead of a term?
Yes — enter your loan amount and interest rate, then adjust your extra monthly payment to see how a higher fixed amount shortens the payoff term.
Is there a free amortization schedule I can download to Excel?
Yes — the ‘Download CSV’ button exports the full amortization table as a CSV file, which opens in Excel, Google Sheets, or Numbers with every payment, principal, interest, and balance row intact.
What’s the difference between amortize, amortized, and amortization?
‘Amortize’ is the verb, ‘amortized’ describes a loan already structured this way (an amortized loan), and ‘amortization’ is the noun for the process or the resulting schedule.
What is reamortization, and when would I reamortize a loan?
Reamortization means recalculating the remaining schedule after something changes the balance or terms — such as a large lump-sum payment or loan recast — spreading the new balance evenly across the remaining term.