Mortgage Calculator

Estimate a fixed-rate mortgage payment, add taxes, insurance, HOA fees or extra principal, and see how the balance, interest and payoff date change over time.

Additional

Housing costs

Property tax(USD / year)

Home insurance(USD / year)

Mortgage insurance(USD / month)

Property / HOA fee(USD / month)

Loan options

Extra principal(USD / month)

One-time extra payment(USD)

Lump-sum date

Closing costs

Interest compounding

First payment date

How to Use the Mortgage Calculator

Enter the home price, down payment, annual interest rate, repayment period, and payment frequency. Those inputs are enough to estimate the mortgage principal-and-interest payment.

Open Additional when you want a fuller housing-cost estimate. You can add property tax, home insurance, mortgage insurance, HOA or property fees, closing costs, extra monthly principal, a one-time lump-sum payment, a first payment date, and the interest-compounding convention.

The result separates the scheduled mortgage payment from optional housing costs, shows the estimated payoff date and lifetime interest, and plots the balance over time. Open the amortization section for payment-by-payment detail or CSV export.

Mortgage Payment Versus Total Housing Payment

The principal-and-interest payment is only the loan repayment. A household's actual housing outflow can also include property tax, homeowners insurance, mortgage insurance, and HOA or property fees.

That distinction matters when comparing homes or loan offers. A mortgage with an affordable principal-and-interest payment can still produce a much higher monthly housing cost once recurring ownership charges are included.

This calculator keeps those optional costs visible as separate components instead of blending them into the loan balance.

**What can make up the mortgage and housing payment**
Component	What it represents	How this calculator treats it
Principal and interest	Repays the mortgage balance and pays the financing cost	Calculated from the loan amount, rate, repayment period, compounding convention, and payment plan
Property tax and home insurance	Ongoing costs of owning the property	Optional annual estimates spread across the selected payment frequency
Mortgage insurance and HOA / property fees	Optional recurring charges that may apply to the loan or property	Entered manually as monthly amounts and kept separate from principal
Extra principal	Additional money applied directly to the outstanding balance	Supports a recurring monthly amount and one dated lump-sum payment
Closing costs	Entered upfront transaction costs	Added to estimated upfront cash, not to the mortgage balance

Why Early Mortgage Payments Are Mostly Interest

A fixed-rate mortgage is amortized: every scheduled payment contains interest and principal, but the mix changes over time.

Interest is calculated from the remaining balance. Early in the loan, that balance is large, so more of each payment goes to interest. As principal falls, the interest charge falls too and more of the same scheduled payment reaches principal.

The balance chart and amortization table make that transition visible. They are often more informative than looking at the payment amount alone.

Down Payment, Loan Amount, and Upfront Cash

The loan amount equals the home price minus the down payment. You can enter the down payment as either a percentage or a currency amount.

A larger down payment reduces the amount financed, which usually reduces both the scheduled payment and lifetime interest when the rate and repayment period stay the same.

The calculator's estimated upfront cash adds the down payment and the closing costs you enter. It is intentionally narrower than a lender's cash-to-close figure, which can also reflect deposits, credits, prepaids, escrow funding, taxes, and other adjustments.

Repayment Period: Lower Payment or Lower Lifetime Interest?

A longer repayment period spreads the principal across more payments. That usually lowers the scheduled payment, but it leaves a balance outstanding for longer and therefore increases the amount of interest paid over the life of the mortgage.

A shorter repayment period usually does the opposite: the payment rises, principal falls faster, and lifetime interest declines.

The right comparison is not only 'Can I make this month's payment?' but also 'How much interest does this repayment period create over the full schedule?'

Monthly, Biweekly, Weekly, and Accelerated Payments

Regular biweekly and weekly plans spread the annual value of the standard monthly principal-and-interest payment across 26 or 52 payments.

Accelerated biweekly uses one half of the monthly principal-and-interest payment every two weeks. Accelerated weekly uses one quarter every week. Those accelerated schedules amount to roughly 13 monthly-payment equivalents per year rather than 12.

Because more principal is paid during the year, an accelerated schedule can shorten payoff and reduce interest. Actual lender definitions, dates, prepayment privileges, and rounding can differ, so use the calculator as a scenario model rather than a replacement for the lender's repayment schedule.

**Payment plans used by the calculator**The schedule below describes the calculator's repayment conventions. A lender may define or round a plan differently.
Plan	Frequency	Scheduled amount	What changes
Monthly	12 payments per year	One standard principal-and-interest payment each month	Baseline repayment schedule
Biweekly	26 payments per year	Monthly principal and interest × 12 ÷ 26	Spreads the same annual scheduled amount across more frequent payments
Accelerated biweekly	26 payments per year	One half of the monthly principal-and-interest payment	Works out to about 13 monthly-payment equivalents each year
Weekly	52 payments per year	Monthly principal and interest × 12 ÷ 52	Spreads the same annual scheduled amount across weekly payments
Accelerated weekly	52 payments per year	One quarter of the monthly principal-and-interest payment	Works out to about 13 monthly-payment equivalents each year

Extra Mortgage Payments: Monthly Versus Lump Sum

Extra principal reduces the balance without replacing the required scheduled payment. Once the balance is lower, future interest is calculated from that smaller amount.

The calculator supports two common strategies: a recurring monthly extra amount and a one-time lump sum on a chosen date. The lump sum is applied to the first scheduled payment on or after that date.

The example below uses a $400,000 home, 20% down, a $320,000 mortgage, a 6.5% annual rate, 30-year repayment, monthly payments, monthly compounding, and a first payment on October 1, 2026. It uses this calculator's cent-rounded amortization model.

**What extra principal changes in one 30-year example**Illustrative calculator output for a $320,000 mortgage at 6.5% with monthly payments and monthly compounding. The lump sum is applied on October 1, 2031.
Scenario	Payment pattern	Extra principal	Total interest	Estimated payoff	Interest saved
Standard schedule	$2,022.62	None	$408,140.64	Sep 2056	—
$200 extra each month	$2,022.62 + $200	$200 monthly	$302,712.79	Feb 2050	$105,427.85
$10,000 lump sum after five years	$2,022.62	$10,000 once	$370,835.13	Oct 2054	$37,305.51

What Interest Compounding Changes

Payment frequency and interest compounding are separate ideas. Payment frequency says how often money is paid. Compounding describes how the quoted nominal annual interest rate is converted into an effective rate over time.

The calculator defaults to monthly compounding. Additional settings also support semi-annual, annual, and daily compounding, then convert that convention to an equivalent rate for the selected payment period.

Use the convention stated in the loan documents when you know it. Mortgage-rate conventions differ between lenders and countries, so two loans displaying the same nominal annual percentage can produce different periodic rates when their compounding conventions differ.

**Interest-compounding options**These choices control how the entered nominal annual rate is converted before the payment schedule is built.
Compounding	Frequency	Calculator treatment
Monthly	12 per year	Default calculator convention and a common basis for fixed-rate mortgage estimates
Semi-annually	2 per year	Useful when a quoted nominal annual rate is compounded twice per year
Annually	1 per year	Converts one annual compounding period to the selected payment frequency
Daily	365 per year	Models a nominal annual rate compounded daily before conversion to the payment period

Taxes, Insurance, Mortgage Insurance, and HOA Fees

Property tax and home insurance are entered as annual estimates. Mortgage insurance and HOA or property fees are entered as monthly estimates. The calculator normalizes those amounts to the selected payment frequency.

These charges do not reduce the mortgage balance. They are displayed because they can materially change the amount a homeowner needs to budget even though they are not principal repayment.

The tool does not guess local tax rates, insurance premiums, mortgage-insurance eligibility, or HOA charges. Enter amounts that match the property and loan scenario you are evaluating.

Closing Costs and Estimated Upfront Cash

Closing costs can be entered as a percentage of the home price or as a direct amount. In this model they are paid upfront and are not added to the mortgage balance.

That makes the calculator useful for comparing the loan payment with the immediate cash required by the scenario, but estimated upfront cash is not the same as an official cash-to-close figure.

If a real loan finances closing costs, uses lender credits, requires prepaid interest or escrow deposits, or applies other adjustments, model those details from the lender's documents rather than assuming this estimate includes them.

How to Read the Amortization Schedule

Each row represents one scheduled payment. Interest is calculated first from the outstanding balance; scheduled principal is the part of the payment that remains after interest.

Recurring extra principal and any one-time lump sum are then applied to the balance. The final columns show the balance that remains after the payment.

The balance chart gives the long view, while the table is useful for checking a particular payment date, seeing how extra principal changes the schedule, or exporting the calculation for further analysis.

Where This Estimate Stops

The calculator models a fixed-rate, fully amortizing mortgage from the values you enter. It does not forecast future interest-rate changes, property values, taxes, insurance premiums, exchange rates, maintenance costs, or borrower income.

It also does not determine eligibility, affordability, mortgage-insurance rules, tax treatment, or prepayment penalties. Those depend on the borrower, property, lender, contract, and jurisdiction.

Use it to compare scenarios consistently. For an actual mortgage, use the rate convention, fees, repayment rules, and payment schedule shown in the lender's documents.

Fixed-Rate Mortgage Formulas

The calculator first finds the amount borrowed, converts the entered nominal annual rate to the selected payment period, then builds an amortization schedule payment by payment.

Loan amount

L = H - D

Equivalent payment-period rate

i_{f} = (1 + \frac{j}{m})^{m / f} - 1

Standard amortizing payment

M = L \frac{i ( 1 + i ) ^{n}}{( 1 + i ) ^{n} - 1}

Zero-interest payment

M = \frac{L}{n}

Interest for payment k

I_{k} = B_{k - 1} i_{f}

Balance after scheduled and extra principal

B_{k} = max (0, B_{k - 1} - P_{k} - E_{k} - Q_{k})

$H$: Home price
$D$: Down-payment amount
$L$: Mortgage principal or loan amount
$j$: Entered nominal annual interest rate as a decimal
$m$: Interest-compounding periods per year
$f$: Scheduled mortgage payments per year
$i_{f}$: Equivalent interest rate for one scheduled payment period
$n$: Number of payments in the amortization calculation
$B_{k}$: Balance after payment k
$P_{k}$: Scheduled principal in payment k
$E_{k}$: Recurring extra principal in payment k
$Q_{k}$: One-time lump-sum principal applied in payment k

Examples

Estimate a standard monthly mortgage

$400,000 home; 20% down; 6.5% annual rate; 30 years; monthly payments; monthly compounding.

Loan amount is $320,000. The estimated principal-and-interest payment is $2,022.62 per month before optional taxes, insurance, mortgage insurance, or property fees.

Add taxes and insurance

Add $4,800 annual property tax and $1,500 annual home insurance to the same monthly mortgage.

The calculator adds $400 per month for property tax and $125 per month for home insurance while keeping those ownership costs separate from principal and interest.

Add $200 of extra principal every month

$320,000 mortgage at 6.5% for 30 years; add $200 per month from the beginning.

In the calculator's monthly-compounding model, total interest falls from $408,140.64 to $302,712.79 and estimated payoff moves from September 2056 to February 2050.

That is about $105,427.85 less interest and 6 years 7 months earlier in this example.

Make a $10,000 lump-sum payment after five years

$320,000 mortgage at 6.5% for 30 years; one $10,000 extra payment on October 1, 2031.

The model applies the lump sum directly to principal. Estimated total interest falls to $370,835.13 and payoff moves to October 2054.

That is about $37,305.51 less interest and 1 year 11 months earlier than the standard schedule.

Compare regular and accelerated biweekly payments

Calculate the same mortgage with Biweekly and Accelerated biweekly selected.

Regular biweekly spreads the annual value of the monthly payment across 26 periods. Accelerated biweekly pays half the monthly amount every two weeks, increasing annual principal repayment.

Use a different interest-compounding convention

Keep the property, down payment, rate, and repayment period unchanged, then compare Monthly and Semi-annually under Interest compounding.

The calculator converts the same nominal annual percentage using each compounding convention, so the periodic rate, scheduled payment, and lifetime interest can change.

Frequently Asked Questions

What does this mortgage calculator calculate?

It estimates the mortgage principal-and-interest payment, optional recurring housing costs, upfront cash, lifetime interest, payoff date, extra-payment savings, remaining balance, and a payment-by-payment amortization schedule.

What is included in the estimated mortgage payment?

The scheduled loan payment contains principal and interest. If you enter them, the displayed housing payment can also include property tax, home insurance, mortgage insurance, HOA or property fees, and recurring extra principal.

What is the difference between home price and loan amount?

Home price is the purchase price you enter. Loan amount is the home price minus the calculated down payment.

Can I enter the down payment as a percentage or an amount?

Yes. Switch the embedded control between percent and the selected display currency. The calculator converts the value into a down-payment amount and percentage for the result.

What is the difference between a mortgage term and an amortization period?

The amortization or repayment period is the time used to pay the balance to zero in the calculator. In markets where a mortgage contract has a shorter term, the rate or contract may need to be renewed before the amortization period ends.

How does accelerated biweekly differ from regular biweekly?

Regular biweekly spreads 12 monthly-payment equivalents across 26 payments. Accelerated biweekly pays half of the monthly principal-and-interest amount every two weeks, which is about 13 monthly-payment equivalents per year.

How do extra monthly mortgage payments save interest?

The extra amount reduces principal. Future interest is then calculated from a smaller balance, which can reduce lifetime interest and move the payoff date earlier.

How does the one-time lump-sum payment work?

Enter an amount and a date. The calculator applies as much of that amount as needed to principal on the first scheduled payment on or after the selected date.

What does the Interest compounding option change?

It changes how the entered nominal annual interest rate is converted to an equivalent rate for the selected payment frequency. Use the convention stated by the lender when you know it.

Does the calculator add mortgage insurance automatically?

No. Mortgage-insurance eligibility, pricing, and cancellation rules differ by loan program and location. Enter a monthly estimate when it applies to your scenario.

Are closing costs financed into the mortgage?

No. This calculator treats entered closing costs as upfront cash. If a real loan finances those costs, its loan amount and payment should be modelled using the lender's figures.

Why might the lender's mortgage payment differ from this estimate?

A lender may use a different compounding convention, day-count method, payment date, fee treatment, insurance rule, or rounding method. The calculator follows the assumptions shown on this page.

Does changing the currency convert the mortgage amount?

No. Currency selection changes display formatting only. Enter the home price, costs, and payments in the same currency.

Can this calculator tell me how much mortgage I qualify for?

No. It calculates repayment scenarios from the values you enter. Borrowing limits and approval depend on income, debts, credit, lender policy, regulation, and other factors not modelled here.