Guide: Finding the Most Accurate 15- & 30-Year Fixed Rate Mortgage Rates Calculator

Making the decision to buy a new home is always exciting, but it can be stressful as well. There are a lot of factors that come into play with buying a home. Before you get started, you will want to make use one of the best 15- or 30- year fixed mortgage rates calculators to calculate monthly payments and more.

Aside from just calculating your monthly payments, a good 30-year mortgage calculator will also tell you how much you will pay in interest over the life of the loan. This is good for those that are looking to save money on their big purchase.

Before you begin working with a 15- or 30-year mortgage calculator, there are definitely a few things that you will want to have in front of you. After all, these 30- and 15-year mortgage rates calculator sites only work well if you input the correct information. The more accurate information you input into the calculator, the more accurate your results will be.

The good news is that a 30-year or 15-year mortgage calculator is really a great way to save yourself some money when it comes to your mortgage loan, but you have to know what to look for. We can help!

15 Year Mortgage Calculator

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In this article, AdvisoryHQ will help you to understand how a 30-year or 15-year mortgage calculator works, and how they can help you to save money on your home purchase. We will also look into some tips for choosing the right mortgage calculator, including what to look for in the best 15- and 30-year mortgage calculator.

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Important Elements to Understand When Using a 15- or 30- Year Mortgage Calculator

We already discussed that you will need some important information for putting correct information into the 15-year mortgage calculator. While all 15- and 30-year mortgage calculator sites are not going to ask for the exact same information, you can count on three specific elements that will be required. These are the basics:

The Principal Amount

The principal amount of a mortgage loan is actually pretty easy to understand when it comes to your 15-year fixed mortgage calculator. When you think about paying toward the principal, you are paying toward the actual amout of the loan, without interest. The principal amount of the loan is the actual face value of your loan. This is what you will want to put into the 30- or 15-year loan calculator when they ask for the principal.

Say your mortgage loan is for $250,000. This means that from day one of the loan, your principal is $250,000. Each time you make a payment toward your mortgage, a portion of this principal will be chiseled away.

The Interest Rate (or APR)

The next important factor for your 15- or 30-year mortgage calculator is the interest rate, or the APR (annual percentage rate). Interest rates are assessed to your account at an annual rate of percentage. These rates vary greatly depending on your creditworthiness and current market rates.

Interest rates can either be variable or fixed. Variable rates may start out lower, but you run the risk of these rates skyrocketing in the future. Fixed rates are generally less risky, but they may be a bit higher from the get-go. Use a 15- or 30-year fixed mortgage rates calculator to determine what is best for you.

The Mortgage Term Length

You should also be aware of the mortgage term length. Most of the 30- and 15-year mortgage rates calculator sites out there are tailored for either a 15- or 30-year mortgage. These are the most common mortgage lengths, although you may find some lenders that will work with different terms.

Your term length is important when using a 30-year or 15-year mortgage calculator because payments and total interest incurred will be completely different with a 15-year term than with a 30-year term. While you may pay far less in interest with a 15-year loan term, monthly payments will be significantly lower if you opt for a 30-year loan term.

Consider looking into a 15-year fixed rate mortgage calculator to see if shorter terms may be a better option for you. According to Investopedia:

“The 30-year-fixed mortgage is practically an American archetype, the apple pie of financial instruments. It is the path that generations of Americans have taken to first-time home ownership. According to the Mortgage Bankers Association, 86% of people applying for purchase mortgages in February 2015 opted for 30-year loans.”

They also go on to say, however, that a 15-year mortgage may have been more suitable for many of these borrowers. Consider checking out a 15-year loan calculator.

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The Purpose of a 15- or 30-Year Mortgage Calculator

So, what exactly does a 15- or 30-year mortgage calculator do? Typically, these calculators are used for one general purpose: to calculate your monthly payments based on the criteria that we already talked about. While the 15-year mortgage rates calculator will only give an estimate, if you input the information correctly, it should be pretty accurate.

You may also want to know just how much interest you will end up paying over the life of the loan, and many 30- and 15-year fixed rate mortgage calculator sites will tell you. Chances are you don’t just have an exorbitant amount of cash lying around to use to buy a home, which means interest in inevitable. Few people actually pay all cash for their home, although this number is on the rise with 43% of all home buyers in 2014 using solely cash.

30 Year Mortgage Calculator

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There are also some 15- and 30-year mortgage calculator sites out there that will offer more details to homebuyers. Some of these thirty-year mortgage calculator tools may go as far as to inclue your homeowners insurance, property taxes, HOA fees, and other relatable fees and charges, giving you a much more accurate estimate for your monthly payments.

Just How Accurate Is a 30-Year or 15-Year Mortage Calculator?

When you look around at different realty sites, you will find that many of them give you an estimated monthly payment for the mortgage. Don’t confuse this with 15-year mortgage rates. The truth is, these estimates are not really very accurate because each individual has their own unique financial profile, meaning they will have their own unique interest rates and other variables to input into a 15-year fixed mortgage calculator.

These numbers are just a blanket estimate for everyone, but chances are that it really isn’t the amount that you would pay. This is why using a dedicated 15- or 30-year mortgage calculator is a much better idea when you want something accurate.

However, as we have said, even the best 15-year mortgage rates calculator is not flawless. Just because a computer is behind the calculation doesn’t mean that there is no room for error. To get the most accurate results from your 15-year mortage calculator, you have to carefully input accurate information.

Without accurate information, you won’t likely get an accurate result with even the best 30- or 15-year fixed rate mortgage calculator. The more details you have about your own personal mortgage loan, the better! Otherwise you are looking at the same problem with the estimates on the realty sites: just a blanket number. A mortgage is not one-size-fits-all.

Typically, a more detailed 15-year mortgage rates calculator offers a more accurate picture of what your payments would be by taking taxes and insurance into account. Even then, however, you may find that it isn’t accurate down to the dollar. It is only intended to be an estimate that helps you make your decision, not the final say.

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Using a 30-Year Fixed Mortgage Rates Calculator to Save Money

One reason that most people turn to either a 15- or 30-year mortgage calculator is so that they will be able to save money in the long run. Not every mortgage lender is created equally, meaning that some will cost you more in the long run.

By comparing several 15-year mortgage rates calculator sites and various lenders, you will be able to find the right combination of term length and interest rates to meet your specific needs.

What to Look for in a 15- or 30-Year Mortgage Calculator

We have already discussed some of the important aspects of both a 30-year and 15-year mortgage rates calculator, so it is time to take a look at the things that you should look for when choosing the right 30-year or 15-year mortgage calculator to meet your specific financial needs. Here are the top three factors to consider:


If you want to get a good idea of your mortgage loan terms and payments, you definitely want to choose an accurate calculator. The best way to do this is by choosing a 15-year mortgage calculator that asks for every little detail about your loan. While this may seem like a waste of time, it will pay off in the long run by giving you the most accurate estimate possible.

Ease of Use

Not every thirty-year mortgage calculator found online is going to be easy to use. If you are not tech savvy, then you will definitely want a 30- or 15-year mortgage rates calculator that spells it out for you. Your calculator should be as easy as inputting the information, clicking, and voila — results! Many of the calculators will even have little prompts that help you to find the correct information, making it easier than ever.


Finally, you will want to consider the reputability of the 30- or 15-year mortgage calculator that you use. Some calculators may be a bit biased to the lender. If you are looking at a lender’s 15-year mortgage rates calculator for your estimate, make sure that you cross reference your results with another 15-year fixed mortgage calculator to ensure that you are getting accurate information.

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Conclusion: How Choosing the Right 30- or 15-Year Loan Calculator Can Make a Huge Difference

Many homebuyers may not truly understand the importance of using a 15- or 30-year mortgage calculator, but it really can make all the difference in the world. There is nothing worse than getting yourself into a financial obligation that you cannot afford. The best way to avoid this is by doing your research ahead of time.

If you choose a basic 30-year mortgage calculator, with only options to input term length, annual percentage rate, and the loan principal, chances are you won’t get an accurate picture of your monthly obligation.

Choosing a detailed 30-year or 15-year mortgage rates calculator with options for all of the details of your mortgage, however, will point you in the right direction for choosing something that you can afford.

If this is your first time to buy a new home, you may want to look into some of the top 30-year and 15-year mortgage calculator sites and play around with the numbers. You may be surprised at the differences between various fifteen- and thirty-year mortgage calculator tools and how that can affect your financial future.

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