15 vs 30 year mortgage calculator
15 vs 30 Year Mortgage Calculator - Compare Payments and Interest
The trade-off
$507
$192,896
Side by side
$2,085
$125,373
$375,373
$1,579
$318,269
$568,269
Choosing between a 15-year and a 30-year mortgage is one of the biggest money decisions in a home purchase, and it comes down to a single trade: the 15-year loan costs more every month but dramatically less over its lifetime. This calculator puts the two loans side by side with your numbers — the same loan amount, each with its own interest rate — so you can see exactly what the shorter term buys you and what it demands from your monthly budget.
Why The 15-Year Loan Wins On Interest
Two forces work together in the 15-year loan's favor. The obvious one is time: interest accrues on your balance every month, and half as many months means far less interest overall. The second is the rate itself — lenders consistently price 15-year loans below 30-year loans, typically by around half a percentage point, because the shorter loan is less risky for them. You can check the current spread between the two on our mortgage rates page.
The combination is powerful. On a typical loan, the 15-year option cuts total interest not by half, as the term alone would suggest, but by roughly 60-65%. The amortization math also means a 15-year loan builds home equity much faster — useful if you may want to borrow against it or sell within a few years.
Why The 30-Year Loan Wins On Flexibility
The 30-year loan's lower required payment is not just about comfort — it's about options. The difference between the two payments can go toward retirement accounts, an emergency fund, or higher-interest debt. And a smaller required payment is easier to carry through a job loss or an expensive year.
There is also a middle path: take the 30-year loan and voluntarily pay extra toward principal. You get most of the interest savings when you can afford it, and a lower obligation when you can't. Our mortgage payoff calculator shows what regular extra payments do to a 30-year loan; note that the 15-year loan still comes out ahead on rate alone.
How To Decide
Lenders will qualify you for either loan using your debt-to-income ratio, but the practical test is stricter: the 15-year payment should fit your budget with room to spare, after retirement savings and an emergency fund. If it only fits when everything goes right, the 30-year loan with optional extra payments is the safer structure. Make sure you compare full monthly costs, not just principal and interest — taxes and insurance are the same either way, and our mortgage payment calculator breaks down the complete PITI payment for any term.
Homeowners already holding a 30-year loan can get to the same place through refinancing into a 15-year term — run those numbers in the refinance calculator.
Frequently asked questions
How does this 15 vs 30 year mortgage calculator work?
Enter the loan amount and an interest rate for each term. The calculator computes both fully amortized monthly payments, the total interest each loan costs over its life, and the two headline numbers: how much more the 15-year loan costs per month and how much interest it saves in total.
Why is the 15-year rate lower than the 30-year rate?
A shorter loan is less risky for the lender - the money is exposed to default and interest-rate changes for half as long. That safety is passed back as a lower rate, historically around half a percentage point below the 30-year average.
Is a 15-year mortgage always cheaper overall?
In total interest, almost always - it combines a lower rate with half the borrowing time. But the required monthly payment is substantially higher, and money locked into house payments isn't available for retirement savings, emergencies, or higher-interest debt. Cheaper overall isn't the same as better for every budget.
Can I get 15-year savings while keeping a 30-year loan?
Mostly, yes. Take the 30-year loan and pay extra toward principal each month - the mortgage payoff calculator shows the effect. You keep a lower required payment for hard months, though the 30-year loan's higher rate means the true 15-year loan still saves somewhat more.
Should I refinance my 30-year mortgage into a 15-year one?
It can make sense if the 15-year payment fits comfortably and you plan to stay in the home. Compare your remaining balance and rate against a new 15-year loan in the refinance calculator, and remember to include closing costs in the comparison.
