Mortgage Calculator: 15, 20 & 30 Year Loan Plans Compared
This simple mortgage calculator, sometimes called a mortgage estimator, goes past principal and interest on any term, including the most popular 30 year mortgage. Property tax alone can swing your real payment by hundreds of dollars depending on where you buy, so this tool factors in your state’s typical tax load, PMI, HOA dues, and insurance, giving you the number you will actually pay, not just the number a basic calculator shows you.
Skip straight to the calculator ↓Your Loan Details
National Average Spotlight
This reflects the blended national average effective property tax rate across all fifty states.
Your Estimated Monthly Payment
Payment breakdown
Balance vs. interest paid over time
Enter your details above to see a plain-language read on your payment.
What If You Paid Extra Toward Principal?
Slide to test an extra monthly payment and see how many years and how much interest this extra payment mortgage calculator says you would save.
What If Your Rate Changes?
| Rate scenario | Interest rate | Monthly P&I | Difference |
|---|
Your 5-Year Equity Projection
| Year | Remaining balance | Principal paid | Interest paid | Equity |
|---|
How to Figure Out a 30 Year Mortgage Payment
I have looked at enough loan estimates to know the number on the first page is rarely the number that shows up in your bank statement six months later. Property taxes get reassessed. Insurance premiums move. PMI comes and goes. A basic mortgage estimator rarely accounts for any of that, which is why this 30 year mortgage calculator with taxes and insurance pulls all of it into one place so you are budgeting for reality, not just for principal and interest.
The formula behind the number
The principal and interest portion uses the standard amortization formula:
| M | Monthly principal and interest payment |
| P | Loan amount (home price minus down payment) |
| r | Monthly interest rate (annual rate divided by 12) |
| n | Total number of monthly payments (loan term in years times 12) |
M = P × [r(1+r)^n] ÷ [(1+r)^n – 1]. On top of that base figure, this 30 year fixed mortgage payment calculator adds your state’s typical property tax, homeowners insurance, PMI (if your down payment is under 20%), and any HOA dues, since a lender will require an escrow account for most of these anyway.
Why a 30-year term is the default choice for most buyers
Spreading a loan over 30 years lowers the monthly principal and interest payment compared to a 15-year or 20-year term, which is why the overwhelming majority of U.S. buyers choose it. The tradeoff is more total interest paid over the life of the loan. Use the loan term toggle above to compare all three side by side against your own numbers.
30-Year vs. 15-Year: Which Fits Your Budget?
Toggle the loan term above to see this comparison update live for your own numbers. As a general pattern, on identical loan amounts and rates:
| Loan term | Typical monthly P&I | Typical total interest | Best for |
|---|---|---|---|
| 30-year fixed | Lowest of the three | Highest of the three | Maximizing monthly cash flow and flexibility |
| 20-year fixed | Middle ground | Middle ground | Buyers who want a faster payoff without the 15-year jump in payment |
| 15-year fixed | Highest of the three | Lowest of the three | Buyers prioritizing total interest savings over monthly flexibility |
How Much House Can I Afford on a 30-Year Mortgage?
The affordability badge above this section uses the 28 percent front-end ratio most conventional lenders reference, comparing your total monthly payment against a reference household income. As a rule of thumb, a 30 year mortgage calculator with taxes and insurance included gives a far more realistic affordability picture than a bare principal-and-interest number, since property tax and insurance can add hundreds of dollars a month depending on your state.
Why property tax matters more than most buyers expect
Property tax is set locally, not federally, so it is the single biggest reason two buyers with identical loan amounts and rates can end up with monthly payments hundreds of dollars apart. States like New Jersey, Illinois, and Connecticut carry effective rates above 2%, while states like Hawaii and Alabama sit well under 1%. A mortgage calculator by state that ignores this will underestimate your real payment by a meaningful margin, which is why this tool lets you select your state, or enter a custom local rate if you know it.
Common mistakes buyers make when estimating a mortgage
- Using the seller’s old tax bill. Many jurisdictions reassess at the new purchase price, so last year’s tax bill on the listing is not necessarily what you will owe.
- Forgetting homestead or residency exemptions. Many states offer a homestead, senior, or disability exemption that lowers your taxable value, but the rules and timelines vary by state and often start the year after you establish residency.
- Skipping PMI removal math. Once you reach 20% equity, you can request PMI removal. Many owners keep paying it for years after they qualify to drop it.
- Ignoring insurance regional swings. Coastal, wildfire-prone, and severe-weather regions can carry meaningfully higher homeowners insurance premiums than the national average used in generic calculators.
Tips for lowering your monthly mortgage payment
- Compare quotes from at least three lenders; a 0.25% rate difference on a $315,000 loan changes your payment by roughly $50 a month.
- Ask your local assessor’s office about homestead, over-65, or disability exemptions you may qualify for.
- Shop homeowners insurance separately from your lender’s default quote; regional carriers often beat national ones on price.
- Use the extra-payment scenario tool above to see how even $100 a month toward principal shortens a 30-year loan by years.
Frequently Asked Questions
What is a 30 year mortgage calculator?
It is a mortgage estimator that projects your full monthly home payment on a 30-year fixed loan, including principal, interest, property tax, homeowners insurance, PMI, and HOA dues, rather than just the base loan payment most basic calculators show.
How accurate is this mortgage calculator with taxes and insurance?
The principal and interest math is exact, based on the standard amortization formula. Property tax, insurance, and PMI are estimates built from typical state rates and market averages, so your actual escrow figures may vary slightly once a lender underwrites your loan.
How do I figure out a mortgage payment by hand?
Use the formula M = P × [r(1+r)^n] ÷ [(1+r)^n – 1], where P is your loan amount, r is your monthly interest rate, and n is your total number of monthly payments, then add your estimated tax, insurance, PMI, and HOA on top.
What down payment do I need to buy a home?
Conventional loans often start around 3 to 5% down, FHA loans typically require 3.5%, and VA loans can allow 0% down for eligible veterans. Putting down less than 20% usually triggers PMI on a conventional loan.
When can I remove PMI on a home loan?
Federal law lets you request PMI removal once you reach 20% equity, and lenders must automatically cancel it at 22% equity based on the original amortization schedule, assuming your payments are current.
Why do property taxes vary so much by state?
Each state, county, and school district sets its own rate, and rates are layered together into one effective property tax bill, which is why states like New Jersey and Illinois run well above the national average while others run well below it.
What is a homestead exemption and does it lower my payment?
A homestead exemption reduces the taxable value of your primary residence, which lowers your property tax bill and therefore your monthly escrow payment. Availability and rules depend entirely on your state.
Should I choose a 15-year or 30-year mortgage?
A 15-year term carries a lower interest rate and far less total interest, but a noticeably higher monthly payment. A 30-year term keeps monthly payments lower and more flexible, which is why most buyers choose it, then make extra principal payments when they can.
How does an extra principal payment affect my mortgage?
Any extra amount applied directly to principal reduces the balance that future interest is calculated on, which shortens your loan term and can save thousands of dollars in interest, as shown in the scenario tool above.
Does this calculator include closing costs?
No, this tool focuses on the ongoing monthly payment. Closing costs typically run 2 to 5% of the loan amount and are a separate one-time expense at signing.
What counts toward my total monthly housing payment?
Principal, interest, property tax, homeowners insurance, PMI (if applicable), and HOA dues, sometimes grouped under the acronym PITI plus HOA. This calculator totals all of them.
Does a 30 year mortgage calculator work the same way for FHA and VA loans?
The principal and interest math is identical for any fixed-rate loan type. FHA loans typically add a mortgage insurance premium instead of conventional PMI, and VA loans often skip mortgage insurance entirely, so treat the PMI field here as an estimate to adjust based on your specific loan program.
Is this tool a substitute for a loan estimate from a lender?
No. This is an educational planning tool. Your actual loan estimate and closing disclosure from a licensed lender are the official figures for your transaction.
References
- Tax Foundation, Property Taxes by State and County – taxfoundation.org/data/all/state/property-taxes-by-state-county
- Consumer Financial Protection Bureau, Owning a Home resources – consumerfinance.gov/owning-a-home
- U.S. Department of Housing and Urban Development, homebuying guidance – hud.gov/topics/buying_a_home
Related State Mortgage Calculators
Property tax is the single biggest reason your payment differs from a national average estimate. Jump straight to your state’s calculator, pre-loaded with local tax context:
Related DexoCalc Tools
This mortgage calculator sits inside a wider set of financial planning tools I have been building out on DexoCalc.
This calculator provides estimates for educational purposes only and is not a loan offer, pre-approval, or substitute for advice from a licensed mortgage professional. Property tax and insurance figures are approximations; confirm exact rates with your local assessor and insurance provider. Sources: Tax Foundation, CFPB.