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15 vs. 30-Year Mortgage Calculator

If you’re looking for a simple and easy-to-use 15 vs. 30-year mortgage calculator, I’ve got you.

I set out to make something super useful, but also straightforward and not overly complicated. Because I know these calculators can get confusing in a hurry.

That’s what you’ll get with this calculator, which compares the 15-year fixed and 30-year fixed side by side.

Use it to quickly determine if one loan type is right for you by comparing mortgage rates, monthly payments, and total interest expense.

Note that a 15-year fixed should come at a sizable discount compared to a 30-year fixed mortgage.

15 vs. 30-Year Mortgage Calculator

Compare a 15-year and 30-year mortgage side by side, including monthly payment, total interest, total cost, and a full amortization schedule for both loans.

Loan Details

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Interest Rates

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15-year rates are typically lower
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Enter your 30-year rate

Full Comparison

Remaining Balance Over Time

Amortization Schedule

Disclaimer: This calculator is for informational and educational purposes only and does not constitute financial, legal, or tax advice. Results are estimates based on fixed interest rates and standard amortization and may not reflect actual loan terms, fees, or outcomes. Consult a licensed mortgage or financial professional before making any financial decisions.

How Much Cheaper Are 15-Year Mortgages?

A shorter-term mortgage should always be cheaper than a longer-term mortgage, but this discount (spread) can vary based on a number of factors and market conditions.

Sometimes it wide and sometimes it’s narrow, but perhaps expect a discount of roughly 0.50% to 0.75% for the 15-year fixed mortgage.

For example, if the 30-year is averaging 6.75%, you might be told a 15-year fixed is going for 6.25%. Or even lower.

Perhaps more importantly, take the time to shop rates to find a lender that can give you a lower rate regardless of the loan type you choose.

Even an .125% of a percentage point can make a big difference, especially after the loan has been held for several years.

You can use my mortgage rate calculator to determine that once you’ve made your decision between the 15-year vs. 30-year mortgage.

[Searching for a home loan? See your options with dozens of lenders fast.]

One thing I’ll point out is you can always make extra payments on a 30-year loan, so if you’re not sure, it’s still an option to save some money and reduce the loan term as well.

With the 15-year, you don’t get that luxury if money gets tight or you change your mind. Of course, the 15-year also keeps you honest and on budget.

Anyway, do the math to get an idea of what payments look like and if you’re comfortable with them.

The savings are always going to look incredible, but also note there is the opportunity cost to money and it could be put to work elsewhere instead.

This is why I mention to look at prepaying a mortgage versus investing instead, as annual returns in the stock market have been double-digits historically.

The same goes for diversification. Putting all your money into a property might not be prudent.

Once it’s in there, it’s hard to get it out. You’ll either need to refinance the mortgage, which kind of defeats the purpose of paying it down faster. Or sell the property.

Read on: Should you only buy a house if you can afford a 15-year mortgage?

Colin Robertson
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