Extra Loan & Mortgage Payment Calculator
Calculate how much time and interest you save by making extra monthly or annual mortgage payments.
- 100% free
- Private in browser
- No signup
- No watermarks
$103,448.79
Money staying in your pocket rather than going to the bank
6.9 Years
83 months shaved completely off your mortgage
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About Extra Loan & Mortgage Payment Calculator
The Extra Loan & Mortgage Payment Calculator shows you the compounding power of paying down loan principal early. By adding even a modest extra monthly payment (e.g., $100 or $200), you can shave years off a 30-year mortgage and keep tens of thousands of dollars in interest in your own pocket.
How to use Extra Loan & Mortgage Payment Calculator
- Enter your original or current loan principal balance.
- Enter your annual fixed interest rate (APR %) and original loan term (e.g. 30 or 15 years).
- Set an extra monthly payment amount applied directly towards principal.
- Review the comparison summary showing exact years shaved off and thousands in interest saved.
Key features
- Side-by-side comparison of standard amortization vs accelerated payoff
- Calculates exact interest savings and net dollar return
- Computes exact years and months shaved off your loan schedule
- 100% private financial calculations performed in-browser with zero telemetry
Frequently asked questions
- How does paying extra principal reduce total loan interest?
- Loan interest is calculated monthly based on your remaining principal balance. When you pay extra towards principal, the remaining balance drops faster, meaning less interest accrues each subsequent month over the remaining life of the loan.
- How much interest can I save by paying an extra $100 a month on a $300,000 mortgage?
- On a 30-year $300,000 mortgage at 6.5% interest, an extra $100/month saves over $40,000 in lifetime interest and pays off the home more than 4 years early.
- Do all banks allow extra principal payments without penalty?
- Most modern residential mortgages and consumer loans in the US, UK, and Europe do not have prepayment penalties. However, always ensure you designate extra payments specifically as "Principal Only" on your lender portal.
- Does this calculator work for auto loans and student loans too?
- Yes. Any fixed-rate amortizing installment loan (including car loans, student loans, and personal loans) behaves identically under extra principal prepayments.
- Is my financial loan data stored or shared?
- No. All calculations are executed strictly within your web browser memory using client-side JavaScript. No numbers are transmitted to remote servers.
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