Personal Finance
Mortgage Calculator
Estimate a fixed-rate mortgage payment with taxes, insurance, PMI, HOA, extra payments, and an amortization schedule.
Free to use — no sign-up or login.
Synced with the percent field.
Added to the year term. Leave 0 for a whole number of years.
Labels the schedule and payoff month. This is not a closing-date model.
Loan amount $320,000.00 · 20.00% down
Down payment is under 20% of the home price. Conventional loans often charge PMI until equity reaches about 20%. Enter an annual premium if you have a quote — this page does not invent one.
Taxes, insurance, PMI, and HOA
These sit on top of principal and interest. Tax and insurance are yearly amounts split across payments. PMI in this estimate stops once the remaining balance is 80% of the original home price.
Yearly amount; the monthly total uses one-twelfth.
Typical conventional PMI is often 0.3%–1.9% of the loan per year when the down payment is under 20%. This estimate drops PMI once the balance reaches 80% of the original home price.
Extra payments
Extra principal shortens the term and cuts interest. It does not change the contractual installment unless you recast with the lender.
Applied every monthly payment. On a biweekly schedule, half of this amount is added to each biweekly payment so the yearly extra stays the same.
Added on the last payment of each 12-month or 26-payment year.
Starting monthly total
Biweekly principal and interest · monthly P&I equivalent
- Principal & interest
- Taxes, insurance, PMI, HOA
- Loan amount
- Total interest
- P&I paid over the loan
- Payoff
- payments
Monthly mix (first payment)
- P&I
- Property tax
- Insurance
- PMI
- HOA
Extra principal in this run: . That is why payoff is earlier than the contractual term.
Amortization schedule
| # | Date | Payment | Principal | Extra | Interest | Balance |
|---|---|---|---|---|---|---|
A mortgage payment is the installment that covers interest on what you still owe and, on an amortizing loan, a slice of principal. This page models a fixed-rate loan from home price, down payment, rate, and term. You can add property tax, homeowners insurance, PMI, HOA dues, and extra principal, then read a yearly or monthly schedule. Lenders name those pieces differently, and none of this is a loan offer.
If you only need a generic installment, the Loan Calculator uses the same annuity formula without housing extras. The Amortization Calculator is the schedule-first cousin. A walkthrough of the payment formula lives in How to Calculate a Mortgage Payment.
What a housing payment is made of
People say “the mortgage” when they mean the whole housing bill. Lenders usually split it. Principal and interest (P&I) are the loan. Property tax and homeowners insurance are often collected into an escrow account and paid when those bills come due. If you put down less than 20% on a typical conventional loan, private mortgage insurance (PMI) may ride along until the loan-to-value ratio drops. Homeowner association dues are usually paid to the association, though some servicers bundle them.
This calculator shows a starting monthly total of those pieces when you fill them in. Tax and insurance are yearly amounts divided by twelve. HOA is already monthly. PMI here is an annual premium you type in — the page will not guess a rate from your credit file. Servicers can round differently, change escrow cushions, or recompute PMI on a current appraisal. Treat the mix bar as a sketch of month one, not a closing disclosure.
How principal and interest are calculated
A fixed-rate amortizing mortgage uses the same annuity formula as other installment loans. Period rate i is the annual rate divided by twelve for a monthly loan, and N is the number of payments (years × 12, plus any extra months). Then p = P · i(1+i)^N / ((1+i)^N − 1). If the rate is zero, p is simply P/N. Each period, interest is charged on the remaining balance; whatever is left of p goes to principal. Early payments are mostly interest. Later ones flip.
The first-payment date you enter labels the schedule. It is not a full closing model: there is no per diem interest, no odd first period, and no points. For a plain loan without house extras, the Loan Calculator is the same math with fewer fields. Compounding on a savings balance is a different problem — that lives on the Compound Interest Calculator.
Down payment, LTV, and PMI
Loan amount is home price minus down payment. The dollar and percent down fields stay in sync when you change either one, or when you change the price while holding the percent. Loan-to-value (LTV) is the loan divided by the home price used here — original purchase price, not a later appraisal.
On many U.S. conventional loans, PMI is required below 20% down and can often be requested off around 80% LTV, with an automatic end near 78% on the original value. This page uses a simple rule: if you enter an annual PMI premium, it is included while the remaining balance is above 80% of the original home price, then it stops. FHA mortgage insurance, lender-paid PMI, and mid-term refis are not modeled. If your down payment is already 20% and you still type a PMI amount, it will still be added until that 80% test is met — so leave PMI at zero when it does not apply.
Extra payments and biweekly schedules
Money you send above the contractual P&I, if the servicer applies it to principal, cuts future interest because the next period’s interest is charged on a smaller balance. The required installment usually stays the same unless you recast. Extra monthly principal is added every month; extra yearly principal lands on the last payment of each 12-month block; a one-time extra hits the payment number you choose.
Biweekly mode takes the monthly P&I, halves it, and applies that amount 26 times a year — one extra monthly equivalent — with interest at annual/26. That is a common illustration, not every servicer’s ledger. Some lenders still accrue monthly and only sweep extra when a full installment piles up. Prepayment penalties are rare on modern U.S. mortgages but still worth reading in the note. Opportunity cost matters too: extra principal is cash you cannot invest elsewhere.
Fifteen years versus thirty at the same rate
The grid below holds the loan amount at $320,000 (a $400,000 home with 20% down) and the rate at 6.5%. Only the term changes. A 15-year schedule raises the monthly P&I and slashes total interest. A 30-year schedule does the opposite. Real 15-year quotes are often a little cheaper on the rate than 30-year quotes; this table does not invent that discount. Affordability still has to clear underwriting, and a lower payment is not free money if you stay in interest longer.
| Term | Monthly P&I | Total interest | Total P&I paid |
|---|---|---|---|
| 15-year fixed | $2,787.54 | $181,757.84 | $501,757.84 |
| 30-year fixed | $2,022.62 | $408,142.36 | $728,142.36 |
Fixed-rate only — what this page skips
This widget is a fixed-rate amortizing loan. It does not simulate an adjustable-rate mortgage (ARM), an interest-only period, negative amortization, or a balloon. It does not shop discount points, origination fees, or credits. Annual tax and insurance increases are omitted; enter a new yearly amount if those bills change. Closing costs, moving, and maintenance are outside the payment. For a rough rent-versus-own cash sketch, use the Rent vs Buy Calculator. For a car note with the same annuity formula, use the Auto Loan Calculator.
Worked example: $400,000 home, 20% down, 6.5% for 30 years
Home price $400,000 with 20% down ($80,000) leaves a $320,000.00 loan. Monthly rate i = 0.065/12, N = 360. The annuity payment is $2,022.62 of principal and interest. The first installment (August 2026 in the default schedule) is about $1,733.33 interest and $289.28 principal. Over the full term, with no extra payments, total interest is about $408,142.36 and the last payment lands in Jul 2056. Adding $200 extra principal each month cuts the run to 281 payments and interest to about $302,713.69 in this engine. Taxes, insurance, PMI, and HOA are extra if you fill those fields; they do not change the P&I formula.
\[ p = 320000\frac{i(1+i)^{360}}{(1+i)^{360}-1}\approx 2022.62 \]
Frequently asked questions
How is the monthly principal and interest calculated?
It is the standard amortizing-loan annuity, not a simple-interest IOU. Split the quoted annual rate by twelve, set N to the number of monthly payments (years × 12, plus extra months), and solve for the level payment that retires the loan amount. Interest each month is that period rate times the remaining balance; the rest of the installment reduces principal. Change the rate or term and the contractual P&I changes; extra principal does not, unless you recast. The How to Calculate a Mortgage Payment tutorial walks the same formula with a $350,000 teaching example.
Does a 20% down payment avoid PMI?
On many U.S. conventional loans, lenders skip borrower-paid PMI at 20% down because the loan-to-value ratio is already 80%. FHA mortgage insurance, some piggyback seconds, and lender-paid PMI follow different rules, so 20% is a habit, not a law. This calculator never invents a premium from your credit file. If you are under 20% down, type an annual quote if you have one. The estimate then drops PMI once the remaining balance reaches 80% of the original home price — a common classroom shortcut, not a promise from your servicer.
What is PITI, and does this include it?
PITI is principal, interest, taxes, and insurance. HOA and PMI are often discussed in the same breath. Fill the tax, insurance, PMI, and HOA fields and the starting monthly total adds them to P&I. Leave them at zero and you get P&I only. Escrow cushions, impound shortages, and mid-year tax reassessments are not in the model. Your Loan Estimate or servicing statement is the live bill.
Do extra payments lower the monthly bill or the interest?
They lower interest and can shorten the term. They do not, by themselves, recast the contractual P&I. Extra principal reduces the balance, so later interest charges shrink and the loan can finish early. A recast or refinance is a separate contract change. Always tell the servicer to apply extra to principal, and watch for how they batch biweekly or “pay ahead” amounts.
How do biweekly payments save money?
Twenty-six half-payments in a year equal thirteen monthly installments. That extra month’s worth of principal, applied steadily, is what shortens the loan in this illustration. Interest here is charged 26 times at annual/26. Some lenders still post interest monthly and only credit extra when a full payment accumulates, so your statement may not match the biweekly table exactly.
Can I model an adjustable-rate mortgage (ARM) here?
No. An ARM needs an initial teaser, a first-reset month, caps, and an index-plus-margin path. This page is fixed-rate only. After an ARM resets you can type the new rate and remaining balance into a fresh run, but that is not a full ARM simulator.
Why don't my lender's numbers match?
Lenders may use daily interest, a different first-period length, odd cents rounding, mortgage insurance that does not drop on original-value LTV, or escrow that includes extra months of cushion. Products also differ by country: amortization conventions in Canada, offset accounts in Australia, and tracker rates in the U.K. are not this U.S.-style fixed annuity. Use the result as a planning estimate, then read the Loan Estimate or offer letter.
References
Assumptions and limitations
This is not lending, tax, or financial advice, and it is not a loan offer. Mortgage products, PMI rules, escrow, and compounding conventions vary by country and lender. Figures are estimates; confirm them with a Loan Estimate or your servicer.
Fixed-rate amortizing loans only. No ARM path, interest-only period, points, or annual tax/insurance inflation. PMI drop is an 80% original-value estimate. Biweekly interest uses annual/26. Extra principal is applied as typed; the contractual installment does not recast.