Finance calculators

Mortgage Rate Calculator

Updated Jul 21, 2026 By Jehan Wadia
Rate Formulas
Loading rate context…
Loan Details
Dollar and % stay in sync.
Auto = price − down; editable.
Prefills a local tax estimate.
Taxes, Insurance & Fees
Applied only while LTV > 80%.
Extra Payments & Biweekly
Affordability & Rent-vs-Buy Inputs
Total Estimated Monthly Payment
$0
Principal & Interest included

Monthly Breakdown

Annual Total Cost
$0
Total Interest Paid
$0
Total Cost of Loan
$0
Loan-to-Value (LTV)
0%

PMI Removal Estimator

Payment Composition
Affordability Context (DTI)
Rent vs. Buy Snapshot
Accelerated Payoff Comparison

Extra Payments

Biweekly Schedule

Step-by-Step Solution
Balance, Principal & Interest Over Time
Amortization Schedule (click a year to expand months)
PeriodDatePaymentPrincipalInterestExtraBalance

Introduction

A mortgage is a loan you take out to buy a home. You pay it back each month over many years, and part of each payment goes toward interest — the fee the bank charges for lending you the money. Knowing your monthly payment before you buy helps you plan your budget and avoid surprises.

This mortgage rate calculator breaks down your full monthly cost, including principal, interest, taxes, insurance, and PMI. Enter your home price, down payment, interest rate, and loan term to get results right away. You can also compare up to three loan scenarios, see how extra payments shorten your loan, check if refinancing saves you money, and find out whether buying discount points is worth the upfront cost. A complete amortization schedule shows exactly where every dollar goes, month by month.

Use this tool to estimate what you can afford, compare your options side by side, and make a smarter decision on one of the biggest purchases of your life.

How to Use Our Mortgage Rate Calculator

Enter details about your home loan below. The calculator will show your monthly payment, total interest, an amortization schedule, and more. You can also compare loans, check refinance savings, and see if buying discount points makes sense.

Payment Tab — Loan Details

Home Price ($): Type the full purchase price of the home you want to buy.

Down Payment ($): Enter the dollar amount you plan to pay upfront. The percentage field will update to match. Not sure how much to put down? Try our down payment calculator to explore different scenarios.

Down Payment (%): Enter your down payment as a percent of the home price. The dollar field will update to match.

Loan Amount ($): This is the home price minus your down payment. It fills in automatically, but you can change it by hand.

Interest Rate / APR (%): Enter the annual interest rate your lender has quoted you. To understand the difference between rate and APR, see our APR calculator.

Loan Term (years): Pick how many years you will take to repay the loan. Choose 10, 15, 20, 25, or 30, or click Custom and type your own number. For a focused look at the most common term, try our 30 year mortgage calculator.

Loan Type: Choose Fixed for a rate that stays the same, or ARM for an adjustable-rate mortgage that can change after a set period.

Credit Score Range: Select the range that matches your credit score. This helps the calculator explain how your score may affect your rate.

Start Month: Pick the month your first mortgage payment will be due.

Start Year: Enter the year your first mortgage payment will be due.

Zip Code: Type your five-digit zip code. The calculator uses it to estimate your local property tax rate.

ARM Fields

These fields appear only when you select ARM as the loan type.

ARM Initial Fixed Period: Choose how many years the starting rate stays locked before it can adjust — 5, 7, or 10 years.

Expected Rate After Adjust (%): Enter the interest rate you expect once the fixed period ends.

Adjustment Cap (%): Enter the most the rate can rise in a single adjustment.

Lifetime Cap (%): Enter the most the rate can ever rise above your starting rate over the life of the loan.

Taxes, Insurance & Fees

Property Tax (annual $): Enter the total property tax you expect to pay each year. Use our property tax calculator if you need help estimating this amount.

Home Insurance (annual $): Enter the yearly cost of your homeowner's insurance policy. Our homeowners insurance calculator can help you estimate this cost.

HOA Fees (monthly $): If your home is in a homeowner's association, enter the monthly fee. If not, leave it at zero.

PMI Rate (annual %): Enter the annual private mortgage insurance rate. PMI applies only when your down payment is less than 20 percent of the home price. For a deeper look at how PMI affects your costs, try our PMI calculator.

Extra Payments & Biweekly

Extra Monthly ($): Enter any extra amount you plan to add to your payment each month to pay off the loan faster. Our mortgage extra payment calculator can show you the full impact of additional payments.

Extra Annual Lump ($): Enter a lump sum you plan to pay once a year toward the loan principal.

Applied In Month: Choose which month of the year you want the annual lump sum applied.

One-Time Extra ($): Enter a single extra payment you plan to make one time only.

One-Time At Payment #: Enter the payment number when you want the one-time extra applied.

Biweekly Payments: Turn this on to see what happens if you pay half your monthly payment every two weeks. This adds up to one extra full payment per year. For a dedicated tool, see our biweekly mortgage calculator.

Affordability & Rent-vs-Buy Inputs

Gross Monthly Income ($): Enter your total household income before taxes each month. This is used to calculate your debt-to-income ratio.

Other Monthly Debts ($): Enter the total of all other monthly debt payments, such as car loans, student loans, or credit cards.

Comparable Monthly Rent ($): Enter what you would pay in rent for a similar home. The calculator compares the cost of renting versus buying. For a more detailed analysis, try our rent vs buy calculator.

Home Appreciation (annual %): Enter the yearly rate you expect your home's value to grow. This is used in the rent-versus-buy comparison.

Refinance Tab

Use this tab to see if refinancing your current mortgage will save you money and how long it takes to break even on closing costs. For a standalone analysis, try our refinance calculator.

Current Loan Balance ($): Enter the remaining balance on your existing mortgage.

Current Rate (%): Enter the interest rate on your current loan.

Current Remaining Term (yrs): Enter how many years are left on your current mortgage.

New Rate (%): Enter the interest rate offered for the new refinanced loan.

New Term (yrs): Enter the number of years for the new loan.

Closing Costs ($): Enter the total closing costs the lender charges to refinance. Our closing cost calculator can help you estimate this figure.

Compare Tab

Use this tab to compare up to three different loan scenarios side by side. For each scenario, fill in the following four fields.

Home Price ($): Enter the home price for that scenario.

Down (%): Enter the down payment as a percentage.

Rate (%): Enter the interest rate for that scenario.

Term (yrs): Enter the loan term in years. The calculator highlights the best value in each row with a green trophy icon.

Points Tab

Use this tab to see if paying for discount points upfront will save you money over time.

Loan Amount ($): Enter the size of your mortgage loan.

Base Rate (%): Enter the interest rate before any points are applied.

Term (yrs): Enter the loan term in years.

Discount Points (0–4): Enter how many points you want to buy. One point equals 1 percent of the loan amount.

Rate Reduction per Point (%): Enter how much each point lowers your interest rate. A common value is 0.25 percent.

Other Controls

High Contrast Toggle: Turn this on if you need a darker background with higher contrast text for easier reading.

Calculate Button: Press this button to run the numbers after you enter or change any values. Results update on screen right away.

Reset Button: Press this button to set all fields back to their original default values.

What Is a Mortgage Rate Calculator?

A mortgage is a loan you take out to buy a home. You pay it back over many years, usually 15 or 30. Each month, part of your payment goes toward the amount you borrowed (called the principal) and part goes toward interest, which is the fee the bank charges for lending you money. A mortgage rate calculator helps you figure out how much your monthly payment will be based on the home price, your down payment, the interest rate, and the loan term. For a broader look at your full mortgage payment, including taxes and insurance, our general mortgage calculator is also helpful.

How Mortgage Payments Work

Your monthly mortgage payment is more than just the loan itself. It usually includes property taxes, homeowner's insurance, and sometimes private mortgage insurance (PMI). PMI is an extra cost added when your down payment is less than 20% of the home price. Once you build enough equity — meaning you owe less than 80% of what the home is worth — PMI goes away. These combined components are often referred to as PITI (principal, interest, taxes, and insurance).

Why Interest Rates Matter

Even a small change in your interest rate can make a big difference over time. A lower rate means you pay less interest over the life of the loan, which saves you thousands of dollars. Your rate depends on things like your credit score, the loan term, and current market conditions. Borrowers with higher credit scores typically get lower rates.

Extra Payments and Paying Off Early

Making extra payments — even small ones — can shorten your loan and cut the total interest you pay. Some people also switch to biweekly payments, which means paying half your monthly amount every two weeks. This adds up to one extra full payment per year and can take years off your mortgage. Use our mortgage payoff calculator or early mortgage payoff calculator to see exactly how much time and money you can save.

Refinancing and Discount Points

Refinancing means replacing your current loan with a new one, usually at a lower rate. This can lower your monthly payment, but it comes with closing costs. You need to stay in the home long enough to make back those costs through savings — our break even calculator can help you figure out that timeline. Discount points let you pay money upfront to get a lower interest rate. One point equals 1% of your loan amount and typically reduces your rate by about 0.25%. If you have existing equity, you may also want to explore a HELOC or home equity loan as alternatives.

Key Terms to Know

  • Principal: The amount of money you borrow.
  • Interest Rate (APR): The yearly cost of borrowing, shown as a percentage.
  • Loan Term: How long you have to pay back the loan.
  • Down Payment: The cash you pay upfront toward the home price. Our down payment calculator can help you decide how much to save.
  • LTV (Loan-to-Value): How much you owe compared to what the home is worth.
  • DTI (Debt-to-Income): How much of your monthly income goes toward debt payments. Lenders like this number to stay below 36%.
  • ARM (Adjustable-Rate Mortgage): A loan where the rate stays fixed for a few years, then can change.
  • Fixed-Rate Mortgage: A loan where the rate never changes.

Formulas used

Monthly Principal & Interest Payment
M = P \cdot \frac{r(1+r)^n}{(1+r)^n - 1}
Total Monthly Payment
\text{Total} = M + \frac{\text{Tax}_{\text{annual}}}{12} + \frac{\text{Insurance}_{\text{annual}}}{12} + \text{HOA} + \text{PMI}_{\text{monthly}}
Monthly PMI
\text{PMI}_{\text{monthly}} = \frac{P \times r_{\text{PMI}}}{12}
Loan-to-Value Ratio
\text{LTV} = \frac{\text{Loan Amount}}{\text{Home Price}} \times 100\%
Debt-to-Income Ratios (Front-End / Back-End)
\text{DTI}_{\text{front}} = \frac{\text{Total Payment}}{\text{Gross Income}} \times 100\%, \quad \text{DTI}_{\text{back}} = \frac{\text{Total Payment} + \text{Other Debts}}{\text{Gross Income}} \times 100\%
Refinance / Points Break-Even
\text{Break-Even (months)} = \left\lceil \frac{\text{Upfront Cost}}{\text{Monthly Savings}} \right\rceil
Future Home Value (Appreciation)
V = P_{\text{home}} \times (1 + r_{\text{appr}})^{t}

Frequently asked questions

How is my monthly mortgage payment calculated?

The calculator uses a standard formula: M = P × [r(1+r)^n] / [(1+r)^n – 1]. P is your loan amount, r is your monthly interest rate (annual rate divided by 12), and n is the total number of payments. It then adds property tax, insurance, HOA fees, and PMI (if applicable) to give you the full monthly cost.

Why does my payment amount change when I adjust the interest rate by just 0.25%?

Interest compounds over many years, so even a small rate change adds up. On a $400,000 loan over 30 years, a 0.25% rate increase can add roughly $55 to $60 per month and tens of thousands of dollars in total interest over the life of the loan.

What is the difference between a fixed-rate and an ARM loan in this calculator?

A fixed-rate loan keeps the same interest rate for the entire term. An ARM (adjustable-rate mortgage) starts with a lower fixed rate for a set period (like 5, 7, or 10 years), then the rate can go up. The calculator shows both phases and caps the adjusted rate based on the lifetime cap you enter.

How does the calculator decide if I need PMI?

If your down payment is less than 20% of the home price, your loan-to-value (LTV) ratio is above 80%. The calculator automatically adds PMI to your monthly payment. Once your balance drops to 80% of the home price, PMI is removed from future payments.

Can I trust the property tax estimate from my zip code?

The zip code gives a rough regional estimate only. Actual property tax rates vary by county, city, and even neighborhood. For an accurate number, check your local tax assessor's website or your most recent tax bill, then type that amount into the property tax field.

How do biweekly payments save me money?

With biweekly payments, you pay half your monthly amount every two weeks. Since there are 52 weeks in a year, you make 26 half-payments, which equals 13 full payments instead of 12. That one extra payment each year goes straight to principal, which cuts years off your loan and reduces total interest.

What does the amortization schedule show?

The amortization schedule lists every payment over the life of your loan. For each payment, it shows how much goes to principal, how much goes to interest, any extra payments, and your remaining balance. Click on a year row to expand and see the monthly details.

How does the refinance break-even calculation work?

The calculator takes your monthly savings from the new lower rate and divides the closing costs by that savings. The result is the number of months it takes to recoup your closing costs. If you plan to stay in your home longer than that, refinancing is likely worth it.

What are discount points and when should I buy them?

A discount point costs 1% of your loan amount and typically lowers your rate by about 0.25%. Buying points makes sense if you plan to keep the loan long enough to pass the break-even point. The Points tab shows exactly how many months that takes and your total net savings.

How does the Compare tab help me pick the best loan?

You can enter up to three different loan scenarios with different prices, down payments, rates, and terms. The calculator shows a side-by-side table of monthly payments, total interest, total cost, and payoff length. A green trophy icon marks the best value in each row so you can see the winner at a glance.

What do front-end and back-end DTI mean?

Front-end DTI is your housing payment (principal, interest, taxes, insurance, HOA) divided by your gross monthly income. Lenders like this under 28%. Back-end DTI adds all your other debts (car loans, student loans, credit cards) to the housing payment before dividing. Lenders like this under 36%.

How accurate is the rent vs. buy comparison?

It gives a simplified snapshot at 5-year and 10-year horizons. It accounts for your mortgage costs, down payment, and home appreciation. However, it does not factor in rent increases, tax deductions, maintenance costs, or investment returns on savings. Use it as a starting point, not a final answer.

Why does the calculator show so much interest at the start of my loan?

Mortgages are front-loaded with interest. In the early years, your balance is high, so most of each payment covers interest. As you pay down the principal over time, the interest portion shrinks and more of your payment goes toward the balance. This is normal for all amortizing loans.

Does this calculator include closing costs in the monthly payment?

No. The main Payment tab calculates your ongoing monthly payment only. Closing costs are a one-time expense paid at the time of purchase. The Refinance tab does factor closing costs into its break-even analysis, but they are not added to your monthly amount.

What happens if I enter a custom loan term like 12 or 25 years?

Click the Custom button under Loan Term, then type any number between 1 and 50. The calculator will compute your payment, amortization schedule, and all other results based on that exact term length.

Can I use this calculator for an investment property or second home?

Yes, the math works the same way. Just enter the price, down payment, rate, and costs for that property. Keep in mind that lenders often charge higher rates for investment properties and may require a larger down payment, so adjust your inputs accordingly.

What does the High Contrast toggle do?

It switches the calculator to a dark background with white text. This makes the screen easier to read for people with low vision or anyone working in a bright environment. It does not change any calculations.

How do I apply a one-time extra payment?

Enter the dollar amount in the One-Time Extra ($) field and specify which payment number it should apply to in the One-Time At Payment # field. The calculator will apply that lump sum to your principal at that exact point and show you the updated payoff date and interest savings.

Does the calculator update automatically when I change a field?

Yes. Most fields trigger an automatic recalculation shortly after you stop typing. You can also press the Calculate button or hit the Enter key on your keyboard to force an immediate update.

Are these results guaranteed by a lender?

No. This calculator provides estimates based on the numbers you enter. Actual loan offers depend on your credit history, lender fees, property appraisal, and other factors. Always get a formal loan estimate from your lender before making a decision.