💰 Finance
Mortgage Calculator
Use this free mortgage calculator to get fast, accurate results.
📝 Your Assumptions
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This mortgage calculator turns your loan amount, interest rate, and term into a real monthly payment, total interest, and total cost. It's for homebuyers comparing offers and homeowners checking whether a refinance actually saves money. A $400,000 loan at 6.5% for 30 years costs $2,528.27 per month and $510,179.20 in total interest — numbers you should know before you sign.
How to Use This Calculator
Three inputs, three outputs — here's how to get numbers you can take to a lender.
1
Enter your loan amount
Type the amount you're borrowing, not the home price. On a $450,000 house with a 20% down payment ($90,000), enter $360,000. If you put down less than 20%, you'll also pay PMI, which this calculator doesn't include.
2
Add your interest rate
Enter the annual percentage rate your lender quoted, such as 6.5 or 7.25. Even a 0.5% difference matters: on a $400,000 30-year loan, 6.5% costs $2,528.27 monthly versus $2,661.24 at 7.0% — $132.97 more every month.
3
Choose your loan term
Select 30 years for the lowest payment or 15 years to pay far less interest. A $400,000 loan at 6.5% costs $510,179.20 in interest over 30 years but only $227,379.60 over 15 years, at a higher $3,485.44 monthly payment.
4
Read your monthly payment
The Monthly Payment figure covers principal and interest only. Your real housing cost adds property taxes, homeowners insurance, and any HOA dues — often $400 to $800 a month on a median-priced US home.
5
Compare total interest and total paid
Total Interest shows what borrowing costs you over the full term; Total Paid is principal plus interest. Run the same loan at 15 years and 30 years side by side — the 15-year option on a $400,000 loan saves $282,799.60 in interest.
What Your Results Mean
Each output tells you something different about the true cost of the loan.
Monthly Payment
This is your principal-and-interest payment, the same every month for a fixed-rate loan. On a $400,000 loan at 6.5% for 30 years, it's $2,528.27. Add taxes and insurance to estimate your full monthly housing cost.
Total Interest
The sum of all interest paid across the loan's life. A $400,000 30-year loan at 6.5% generates $510,179.20 in interest — more than the amount you borrowed. Shortening the term or lowering the rate cuts this figure fastest.
Total Paid
Principal plus interest over the full term. For that $400,000 loan at 6.5% for 30 years, Total Paid is $910,179.20. Seeing this number is why a lower rate matters more than a slightly lower home price.
Amortization
Early payments are mostly interest; later payments are mostly principal. On a $400,000 loan at 6.5%, month one sends about $2,166.67 to interest and only $361.60 to principal — the split flips around year 19.
Term Length Trade-off
A 15-year loan raises the monthly payment but slashes total interest. On $400,000 at 6.5%, 15 years costs $3,485.44 monthly but just $227,379.60 in interest — $282,799.60 less than the 30-year option.
Rate Sensitivity
Small rate changes move your payment more than you'd expect. On a $400,000 30-year loan, 6.0% costs $2,398.20 monthly and 7.0% costs $2,661.24 — a $263.04 gap for one percentage point.
Key Terms
Principal
The amount you borrow, separate from interest. On a $400,000 mortgage, the principal starts at $400,000 and shrinks with each payment.
Interest Rate
The annual cost of borrowing, expressed as a percentage of the loan balance. A 6.5% rate on $400,000 means roughly $26,000 in interest in year one.
Amortization
The schedule that splits each payment between interest and principal until the loan is paid off. It's why your balance drops slowly at first and quickly near the end.
Loan Term
How long you have to repay the loan, usually 15 or 30 years. A shorter term means higher monthly payments but far less total interest.
APR
The annual percentage rate includes the interest rate plus lender fees, so it's higher than the quoted rate. Comparing APRs across lenders shows the real cost of each offer.
❓ Frequently Asked Questions
At a 6.5% fixed rate for 30 years, a $400,000 mortgage costs $2,528.27 per month in principal and interest. Over the full term you'd pay $510,179.20 in interest and $910,179.20 in total. Drop the rate to 6.0% and the payment falls to $2,398.20 — a savings of $130.07 a month, or $46,825.20 over 30 years. Choose a 15-year term at 6.5% instead and the payment jumps to $3,485.44, but total interest drops to $227,379.60, saving $282,799.60. Remember that these figures exclude property taxes, homeowners insurance, and PMI, which commonly add $400 to $800 a month. To see how a different loan size changes things, run the numbers in the loan calculator, or use the auto loan calculator if you're weighing a car payment against a bigger mortgage.
A 15-year mortgage saves enormous interest but raises your monthly payment by roughly 38%. On a $400,000 loan at 6.5%, the 15-year payment is $3,485.44 versus $2,528.27 for 30 years — $957.17 more each month. In exchange, total interest falls from $510,179.20 to $227,379.60, a savings of $282,799.60. The break-even question is whether you can comfortably afford the higher payment and whether you'd invest the $957 monthly difference elsewhere. If you can't handle the higher payment during a job loss or emergency, the 30-year loan's flexibility is worth the extra interest. A middle path: take the 30-year loan and make extra principal payments when possible. Compare both scenarios in this mortgage calculator, then check the personal loan calculator if you're deciding between paying down a mortgage and clearing higher-rate debt first.
On a $400,000 30-year loan, half a percentage point costs $132.97 per month and $47,869.20 over the full term. At 6.5% the payment is $2,528.27 with $510,179.20 in total interest; at 7.0% it's $2,661.24 with $558,048.40 in interest. That's real money for a difference many buyers treat as trivial. Over a full percentage point — 6.0% versus 7.0% — the gap widens to $263.04 monthly and $94,694.40 total. This is why shopping multiple lenders matters: a single point of rate can be worth more than a $20,000 discount on the home price. Get quotes from at least three lenders on the same day, since rates move daily. Once you have your numbers, use this mortgage calculator to compare each offer side by side, and the loan calculator to see how the same rate behaves on a smaller loan.
Mortgage interest is calculated on your remaining balance, so the largest balance produces the largest interest charge. On a $400,000 loan at 6.5%, the monthly rate is 0.5417% (6.5% divided by 12). Month one: $400,000 × 0.005417 = $2,166.67 in interest, leaving only $361.60 of your $2,528.27 payment to reduce principal. By year 15, the balance is roughly $264,000 and interest takes about $1,430, so more than $1,000 goes to principal. The crossover — where principal finally exceeds interest — happens around year 19 on a 30-year loan. This front-loaded structure is why extra payments early save so much: an extra $200 a month starting in year one can cut years off the loan. Model it here, and if you're paying off other debt first, the personal loan calculator can show which balance to attack.
This calculator shows principal and interest only. Your actual monthly housing payment typically also includes property taxes, homeowners insurance, and possibly PMI and HOA dues. On a $400,000 home, property taxes at 1.2% of value run about $400 a month, homeowners insurance around $150, and PMI — required with less than 20% down — often $150 to $250. HOA fees in a condo or planned community add $100 to $500 or more. That means a $2,528.27 principal-and-interest payment could become $3,200 to $3,400 out of pocket. Lenders qualify you on the full figure, not just P&I, using debt-to-income ratios — usually a maximum of 43% to 50%. Estimate your complete payment before house hunting. For other borrowing costs, the auto loan calculator handles car payments the same way.
You need a 20% down payment to avoid private mortgage insurance on a conventional loan. On a $400,000 home, that's $80,000, leaving a $320,000 mortgage. At 6.5% for 30 years, the payment is $2,022.62 with $408,143.36 in total interest. Put only 10% down ($40,000) and you borrow $360,000, pay $2,275.44 monthly, and owe $459,201.28 in interest — plus PMI of roughly $150 to $250 a month until you reach 20% equity. On an FHA loan, the down payment minimum is 3.5% but mortgage insurance premiums usually last the life of the loan unless you refinance. PMI on conventional loans ends automatically at 22% equity and can be canceled at 20% upon request. Run your down payment scenarios in this mortgage calculator, and the loan calculator for smaller borrowing needs.
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