See how extra payments can help you pay off your mortgage faster. Compare strategies and calculate interest savings.
Time Saved
9y 7m
Faster payoff
Interest Saved
$131,411
Adding $300 to each monthly payment.
| Extra/Month | Time Saved | Interest Saved | New Payoff |
|---|---|---|---|
| $100 | 4y 3m | $60,159 | Jan 2052 |
| $250 | 8y 6m | $117,351 | Oct 2047 |
| $500 | 12y 11m | $173,463 | May 2043 |
| $1,000 | 17y 9m | $230,321 | Jul 2038 |
Biweekly Payments
5 years, 10 months faster
Save $81,376
$300/month Extra
9 years, 7 months faster
Save $131,411
$3600/year Extra
9 years, 4 months faster
Save $126,901
Round Up
Round your payment to the nearest $100 for easy extra principal.
Tax Refunds
Apply annual tax refunds as lump sum principal payments.
Specify Principal
Label extra payments as "principal only" to ensure they reduce balance.
Automate
Set up automatic extra payments so you don't forget.
Time Saved
9y 7m
Faster payoff
Interest Saved
$131,411
See how increasing extra payments accelerates your payoff and saves interest
2 insights based on your inputs
You'll pay off 9 years earlier and save $131,411 in interest!
You'll save more than 30% of your current balance in interest - excellent strategy!
Explore other tools that might help
Make extra principal payments (even $100/month helps). Switch to biweekly payments (makes 13 payments/year). Apply tax refunds or bonuses as lump sums. Round up your payment. Refinance to a shorter term. Avoid resetting the clock when refinancing.
Consider your mortgage rate vs investment returns, tax benefits (interest deduction), emergency fund status, other debt rates, and retirement savings. Generally, pay off if rate > 5-6% or you want peace of mind. Invest if rate < 4% and you're comfortable with debt.
Instead of 12 monthly payments, you make 26 half-payments (every two weeks). This equals 13 full payments per year instead of 12. The extra payment goes to principal, typically saving 4-6 years and tens of thousands in interest on a 30-year mortgage.
On a $300K mortgage at 7%, $200/month extra saves $95K in interest and pays off 8 years early. Even $50/month saves $25K and 2 years. The earlier you start, the more you save due to compound interest working in reverse.
Most conventional loans have no prepayment penalty. Some loans (especially older ones or certain private loans) may have penalties for the first 3-5 years. Check your loan documents or contact your servicer. Federal law limits prepayment penalties.
Calculations are run entirely in your browser. No inputs are sent to our servers and no account is required. Formulas follow standard US definitions from the IRS and the CFPB where applicable; international users should confirm local tax and regulatory rules apply.
This is a software engineering tool, not financial advice. Run the math here, then take the result to a certified financial planner, CPA, or your bank before making a decision that materially affects your money.
US consumer finance regulator; authoritative on mortgage disclosures, APR rules, credit cards.

Full-stack software engineer specializing in embedded systems, web architecture, and AI/ML. Founder of Practical Web Tools. Built the gesture-controlled drone IP acquired by KD Interactive (Aura Drone, sold on Amazon).
Time Saved
9y 7m
Faster payoff
Interest Saved
$131,411