Amortization Calculator

See your complete loan payment schedule and discover how extra payments can cut years off your mortgage.

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Loan Details

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Interest Rate %
Loan Term
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Extra Monthly $0/mo

Summary

Monthly Payment
$0
  • Loan Amount
  • Total Interest Paid
  • Total Cost of Loan
  • Payoff Date

Full Payment Schedule

# Date Payment Principal Interest Balance

What Is Amortization?

Amortization is the process of paying off a loan through regular payments over time. Each payment is split between interest (what the lender charges) and principal (reducing your balance). Early in the loan, most of each payment goes to interest — toward the end, most goes to principal.

Why Interest Is Front-Loaded

Every monthly payment is calculated on your current balance, not your original loan amount. In month one of a 30-year loan, your balance is at its highest, so the largest possible share of that fixed payment goes to interest — often 75–85% of it. As the balance shrinks month by month, the interest portion shrinks with it and the principal portion grows, even though your total payment stays the same on a fixed-rate loan. This is why a 30-year loan feels like it "barely moves" the balance for the first several years — you're paying mostly for the use of the money, not paying it down.

How the Schedule Shifts Over Time

The crossover point — where more of your payment goes to principal than interest — typically lands around the halfway mark of the loan's term on a standard 30-year fixed loan, though it depends on your rate. Scroll through the table above and watch the principal and interest columns cross; that's the moment your equity starts building noticeably faster each year.

Why Extra Payments Save So Much

Because interest is calculated on your remaining balance, every extra dollar of principal you pay today reduces the interest that accrues for every remaining month of the loan — not just this one. That compounding effect is strongest early in the loan, when the balance (and therefore future interest) is largest. A single extra $200/month payment on a 30-year loan at 7% can cut 4–6 years off the loan and save over $60,000 in interest. Use the slider above to see the exact savings for your loan amount and rate.

How to Use This Table

Scroll through the full schedule to see exactly how much of each payment goes to interest vs. principal each month. Notice how the interest portion decreases as the balance falls — that's amortization at work.

Should I Refinance Instead of Making Extra Payments?

If rates have dropped since you got your loan, refinancing can lower your base payment and reduce interest even without extra payments. Use our Refinance Calculator to see your breakeven point.

Amortization Calculator FAQ

Interest is calculated on your current balance, which is highest at the start of the loan. Since your monthly payment is fixed, the largest share of it in month one goes to interest — often 75–85% on a 30-year loan. That share shifts toward principal every month as the balance falls.
It depends on your rate and how early you start, but the effect compounds — every extra dollar reduces the interest charged on that dollar for every remaining month of the loan. An extra $200/month on a $320,000 loan at 7% can save tens of thousands of dollars and shave years off the payoff date. Use the extra payment slider above to see your exact numbers.
This "crossover point" typically lands around the midpoint of a standard 30-year fixed loan, though it shifts earlier on shorter terms or lower rates. Scroll through the schedule above and watch the principal and interest columns to find the exact month for your loan.
If your current rate is already competitive, extra payments are the simpler way to save interest and shorten your term. If rates have dropped meaningfully since you got your loan, refinancing can lower your base payment on top of any extra payments. Compare both with our Refinance Calculator.
Yes — even a single extra payment a year, spread as roughly 1/12th extra per month, can cut several years off a 30-year loan because it directly reduces the principal balance interest is calculated on for the rest of the loan.