Extra Payment Calculator –
Pay Off Faster, Save Thousands
Find out exactly how much interest you save and how many years you cut from your loan by adding extra monthly, yearly, or one-time payments to your mortgage.
Extra Payment Calculator
Enter your loan details and extra payment amounts to see how much you save.
Estimates only. Assumes all extra payments applied to principal. Check your loan agreement for prepayment terms before making extra payments.
Amortization Comparison
| Period | Payment | Extra | Principal | Interest | Balance | Orig. Balance |
|---|---|---|---|---|---|---|
| Click Calculate Savings to generate the comparison schedule. | ||||||
How to Use the Extra Payment Calculator
Model any extra payment scenario in under a minute — then compare savings side by side.
Enter Loan Details
Input your remaining balance, interest rate, and remaining loan term.
Add Extra Payments
Enter extra monthly, yearly, or a one-time lump-sum payment amount.
See Your Savings
Instantly see total interest saved and how many years you cut from the loan.
Review the Schedule
Check the month-by-month amortization showing your extra payments at work.
Three Ways to Make Extra Mortgage Payments
Any extra principal payment saves you interest — but the method and timing matter.
Adding even $100–$200 per month consistently reduces your balance year-round, compounding your interest savings over decades.
A once-a-year lump sum from a tax refund, bonus, or gift applied to principal can shave years off your loan with minimal lifestyle impact.
Applied immediately in month one, a large lump-sum payment delivers maximum interest savings because it reduces the principal from the very start.
Use all three together — a lump sum upfront, monthly extras, and annual contributions. This calculator models all three simultaneously for maximum accuracy.
Paying half your monthly payment every two weeks results in one extra full payment per year automatically — equivalent to adding about 8% of your monthly payment extra each month.
Paying down a 6.75% mortgage gives a guaranteed tax-equivalent return. Compare this to expected investment returns to decide which path fits your financial goals.
How Much Does $100/Month Extra Save on a $320,000 Loan?
Based on a 30-year fixed mortgage at various interest rates. Extra payments applied monthly to principal.
| Extra / Month | @ 5.50% | @ 6.00% | @ 6.75% | @ 7.50% |
|---|---|---|---|---|
| $100/mo | $27,800 saved 3 yr 4 mo early |
$32,500 saved 3 yr 7 mo early |
$39,600 saved 4 yr early |
$47,200 saved 4 yr 3 mo early |
| $200/mo | $48,700 saved 6 yr 2 mo early |
$57,100 saved 6 yr 6 mo early |
$68,900 saved 7 yr early |
$81,000 saved 7 yr 5 mo early |
| $500/mo | $95,300 saved 12 yr 4 mo early |
$110,400 saved 12 yr 10 mo early |
$131,000 saved 13 yr 6 mo early |
$151,800 saved 14 yr early |
| $1,000/mo | $144,600 saved 18 yr 8 mo early |
$164,700 saved 19 yr 2 mo early |
$190,800 saved 19 yr 9 mo early |
$214,300 saved 20 yr 1 mo early |
Frequently Asked Questions
Everything you need to know about making extra mortgage payments.
How do extra mortgage payments work?
Is it better to pay extra monthly or as a lump sum?
Does the calculator include prepayment penalties?
Will my lender automatically apply extra payments to principal?
What's the best time to start making extra payments?
Can I use this for an existing mortgage?
Why Use Our Extra Payment Calculator?
Built for homeowners who want to see the real impact of paying down their mortgage faster.
Real-Time Results
Every figure updates instantly as you type — no page reloads needed.
True Side-by-Side View
See your original loan vs. the extra-payment scenario in one clean comparison.
Three Payment Types
Model monthly, yearly, and one-time extra payments — all at once or separately.
Full Amortization
Month-by-month schedule shows exactly where your extra payments go each period.
100% Private
Your loan details never leave your browser. Nothing is stored or uploaded.
Free Forever
No subscriptions, no trials, no limits — unlimited calculations at no cost.
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