Mortgage Calculator
Estimate your monthly mortgage payment, total interest, and total cost for any home loan amount, rate, and term.
What is a mortgage calculator?
A mortgage calculator is a tool that estimates your monthly home-loan payment from four numbers: the home price, your down payment, the interest rate, and the loan term. Enter them above and you get the Monthly payment (P&I), the Loan amount, the Total interest you will pay, and the Total cost of loan.
Use it before you talk to a lender, so you walk in knowing what a $400,000 house costs per month at the rate you are quoted — and how much a bigger down payment, a shorter term, or a quarter-point lower rate would change that number.
What is in a monthly mortgage payment?
The figure this calculator shows is principal and interest (P&I) — the part that repays the loan. Your real monthly housing bill usually has more in it, and the full amount is often called PITI:
| Component | What it is | How it changes |
|---|---|---|
| Principal | Repays the amount you borrowed | Rises every month (see the amortization table below) |
| Interest | What the lender charges on the balance | Falls every month |
| Taxes | Property tax, often collected into an escrow account | Set by your local taxing authorities; can change each year |
| Insurance | Homeowners insurance, often escrowed | Set by your insurer; can change at renewal |
| PMI / MIP | Mortgage insurance; on a conventional loan it is usually required with less than 20% down | Shown on your Loan Estimate; PMI can be cancelled later (see the FAQ) |
| HOA dues | If the property is in an association | Set by the association |
For the $400,000 example on this page, the P&I payment is $2,075.51. With an assumed $4,000 a year of property tax and $2,000 of insurance (use your own figures), escrow adds $333.33 and $166.67, for about $2,575.51 a month. With 10% down instead of 20%, the loan is $360,000, the P&I alone is $2,334.95, and PMI is usually added on top. Budget on the full payment, not on P&I.
15-year vs 20-year vs 30-year: the same loan, three ways
The loan term is the single biggest lever after the rate. Here is a $320,000 loan at 6.75% over each common term:
| Term | Monthly P&I | Total interest | Total paid |
|---|---|---|---|
| 30 years | $2,076 | $427,185 | $747,185 |
| 20 years | $2,433 | $263,960 | $583,960 |
| 15 years | $2,832 | $189,708 | $509,708 |
The 15-year loan costs $756 more per month but saves $237,477 in interest — more than half. Fifteen-year loans also usually carry a lower rate: in Freddie Mac's survey for October 15, 2026, the 30-year average was 7.40% and the 15-year average 6.71%, which on this loan means $2,215.62 a month over 30 years or $2,824.62 over 15. The trade-off is flexibility: a 30-year loan with voluntary extra payments lets you pay early without the obligation. See the 15-year vs 30-year mortgage guide.
How much difference does the interest rate make?
Rates move daily and lenders quote different numbers to the same borrower. On the same $320,000, 30-year loan:
| Rate | Monthly P&I | Total interest |
|---|---|---|
| 5.50% | $1,817 | $334,093 |
| 6.00% | $1,919 | $370,682 |
| 6.50% | $2,023 | $408,142 |
| 6.75% | $2,076 | $427,185 |
| 7.00% | $2,129 | $446,428 |
| 7.40% | $2,216 | $477,622 |
| 7.50% | $2,237 | $485,495 |
| 8.00% | $2,348 | $525,297 |
Every quarter-point is worth about $53 a month here, or roughly $19,000 over the life of the loan. That is why it pays to get quotes from more than one lender and to compare the APR (which includes lender fees) as well as the rate.
How much house can you afford?
A traditional rule of thumb is the 28/36 rule: keep your full housing payment (PITI) under 28% of gross monthly income, and all debt payments together — housing plus car loans, student loans and credit-card minimums — under 36%. It is a guideline, not a lending rule; lenders set their own limits.
| Gross annual income | Max housing payment (28%) | Max total debt (36%) |
|---|---|---|
| $75,000 | $1,750 / month | $2,250 / month |
| $100,000 | $2,333 / month | $3,000 / month |
| $150,000 | $3,500 / month | $4,500 / month |
Working backwards at 6.75% over 30 years, a $2,000 P&I budget supports a loan of about $308,000; $2,500 supports about $385,000; $3,000 supports about $463,000 — before taxes and insurance. The rule uses gross income, but the payment comes out of take-home pay, which the paycheck calculator shows.
Fixed-rate vs adjustable-rate mortgages
This calculator assumes a fixed-rate loan: the rate and the P&I payment never change. An adjustable-rate mortgage (ARM) — a 5/1 or 7/6 ARM, for example — starts with a fixed rate for 5 or 7 years and then adjusts at set intervals with the market, subject to caps. ARMs can make sense if you expect to sell or refinance before the fixed period ends; if you plan to stay, weigh the lower starting rate against the risk of higher payments later. To model an ARM here, run the fixed period at the intro rate, then re-run the remaining balance at a higher rate (see the FAQ below).
Loan types at a glance
- Conventional — not government-backed; with less than 20% down, PMI is usually required and can be cancelled later. Loans above the FHFA conforming limit (which changes every year) are jumbo loans.
- FHA — insured by the Federal Housing Administration, with its own upfront and annual mortgage-insurance premiums (MIP).
- VA — for eligible service members, veterans and surviving spouses; no down payment or monthly mortgage insurance required, and a one-time funding fee that is waived for borrowers receiving VA compensation for a service-connected disability.
Formula
Every fixed-rate mortgage in the United States is priced with the same amortization formula:
M = P × r × (1 + r)n ÷ ((1 + r)n − 1)
- M = monthly payment (principal and interest only)
- P = loan amount = home price − down payment
- r = monthly interest rate = annual rate ÷ 12 ÷ 100 (6.75% → 0.005625)
- n = number of monthly payments = years × 12 (30 years → 360)
The formula finds the one fixed payment that, made 360 times, exactly retires the balance with interest. Total cost of loan = M × n, and total interest = total cost − P. If the rate is 0%, the payment is simply P ÷ n and the total interest is exactly $0.00. If the down payment is negative, or equal to or larger than the price, there is no loan to calculate and the results show a dash.
Why the early payments are almost all interest
Interest is charged each month on the remaining balance. In month one you owe the full $320,000, so at 0.5625% per month the interest is $1,800.00 and only $275.51 of the $2,075.51 payment reduces the loan. As the balance falls, the interest portion falls and the principal portion rises — slowly at first, then quickly. That is why the balance on a 30-year loan barely moves in the first few years, why selling within two or three years often means paying closing costs twice for very little equity, and why extra principal payments early on are so powerful.
Worked example
A home priced at $400,000 with a $80,000 (20%) down payment, financed at 6.75% over 30 years:
- Loan amount P = $400,000 − $80,000 = $320,000
- Monthly rate r = 6.75 ÷ 12 ÷ 100 = 0.005625
- Number of payments n = 30 × 12 = 360
- (1 + r)n = 1.005625360 ≈ 7.533245
- M = 320,000 × 0.005625 × 7.533245 ÷ (7.533245 − 1) ≈ $2,075.51 per month
- Total paid over 30 years = M × 360 = $747,185.01 (the calculator multiplies the unrounded payment; $2,075.51 × 360 gives $747,183.60)
- Total interest = $747,185.01 − $320,000 = $427,185.01
The calculator shows those four totals. The two tables below were worked out month by month from the same $2,075.51 payment.
Amortization schedule — the first year
| Month | Payment | Interest | Principal | Balance after |
|---|---|---|---|---|
| 1 | $2,075.51 | $1,800.00 | $275.51 | $319,724.49 |
| 2 | $2,075.51 | $1,798.45 | $277.06 | $319,447.42 |
| 3 | $2,075.51 | $1,796.89 | $278.62 | $319,168.80 |
| 4 | $2,075.51 | $1,795.32 | $280.19 | $318,888.61 |
| 5 | $2,075.51 | $1,793.75 | $281.77 | $318,606.85 |
| 6 | $2,075.51 | $1,792.16 | $283.35 | $318,323.49 |
| 7 | $2,075.51 | $1,790.57 | $284.94 | $318,038.55 |
| 8 | $2,075.51 | $1,788.97 | $286.55 | $317,752.00 |
| 9 | $2,075.51 | $1,787.36 | $288.16 | $317,463.84 |
| 10 | $2,075.51 | $1,785.73 | $289.78 | $317,174.06 |
| 11 | $2,075.51 | $1,784.10 | $291.41 | $316,882.66 |
| 12 | $2,075.51 | $1,782.46 | $293.05 | $316,589.61 |
After a full year of payments totalling $24,906, the balance has dropped by just $3,410 — 86% of the first year went to interest.
Where the loan stands at each five-year mark
| End of year | Remaining balance | Principal paid so far | Interest paid so far |
|---|---|---|---|
| 1 | $316,590 | $3,410 | $21,496 |
| 5 | $300,402 | $19,598 | $104,933 |
| 10 | $272,963 | $47,037 | $202,025 |
| 15 | $234,545 | $85,455 | $288,138 |
| 20 | $180,756 | $139,244 | $358,879 |
| 25 | $105,445 | $214,555 | $408,099 |
| 30 | $0 | $320,000 | $427,185 |
The halfway point in time (year 15) is nowhere near the halfway point in payoff: only 27% of the principal has been repaid. The balance first falls below half the loan ($160,000) with payment 259, 21 years and 7 months in — that is, during year 22.
How to use this calculator
- Enter the full purchase price of the home.
- Enter your down payment in dollars. On a conventional loan, less than 20% down usually means paying PMI on top of the payment shown.
- Enter the interest rate your lender quoted. If you are still shopping, try 6.5%, 7% and 7.5% to see how sensitive the payment is.
- Enter the loan term in years; 30, 20 and 15 years are the usual choices.
- Read the Monthly payment (P&I), Loan amount, Total interest and Total cost of loan. The results update as you type.
Remember that the payment shown is principal and interest only. Add property tax, homeowners insurance, mortgage insurance (if any) and any HOA dues to get your true monthly housing cost.
What this calculator does not do
- It does not add property tax, insurance, PMI or MIP, or HOA dues.
- It does not print a schedule for your loan or model extra payments, points or closing costs; the tables for those on this page were worked out separately.
- It assumes one fixed rate for the whole term, so it cannot follow an ARM after it adjusts.
- It uses the interest rate, not the APR.
- It shows no result if the down payment is negative or at least the price of the home.
Paying it off faster: extra payments and biweekly plans
Because interest is charged on the balance, any extra dollar you send is applied to principal and stops earning interest for the lender for the rest of the loan. On the $320,000, 6.75%, 30-year example, worked out month by month:
| Extra principal per month | Paid off in | Total interest | Interest saved |
|---|---|---|---|
| $0 | 30 years | $427,185 | — |
| $100 | 26 years 2 months | $361,337 | $65,848 |
| $200 | 23 years 4 months | $315,107 | $112,078 |
| $500 | 17 years 10 months | $231,115 | $196,070 |
A biweekly payment plan (half a payment every two weeks) makes 26 half-payments, or 13 full payments, a year. Adding one-twelfth of the payment ($172.96) to principal each month does the same: it pays this loan off in 24 years and saves about $101,000 of interest. Mark extra amounts "apply to principal" and check for a prepayment penalty.
Discount points: paying for a lower rate
One point costs 1% of the loan amount ($3,200 here). How much it lowers the rate depends on the lender, the loan and the market, so ask for quotes with and without points. If one point took this loan from 6.75% to 6.50%, the payment would fall from $2,075.51 to $2,022.62, about $52.90 a month, and the point would pay for itself in about 60 months. Points make sense only if you will keep the loan well past the break-even.
Refinancing: the break-even test
Refinancing replaces your loan with a new one, with its own closing costs on a new Loan Estimate. Divide the closing costs by the monthly saving: a $300,000, 30-year loan refinanced from 7.25% to 6.25% drops from $2,046.53 to $1,847.15, saving $199.38 a month, so $6,000 of costs breaks even in about 30 months. Compare the total interest too — restarting a 30-year clock can cost more overall even when the payment drops.
Related tools
- Savings goal calculator — saving for the down payment
- Compound interest calculator — what investing a payment difference could grow to
- Income tax calculator — your federal income tax
Sources
- Freddie Mac — Primary Mortgage Market Survey (30-year 7.40% and 15-year 6.71%, October 15, 2026)
- Consumer Financial Protection Bureau — When can I remove private mortgage insurance (PMI) from my loan?
- Consumer Financial Protection Bureau — What are discount points and lender credits and how do they work?
- U.S. Department of Veterans Affairs — VA funding fee and loan closing costs
Frequently asked questions
What is included in my monthly mortgage payment?
A typical U.S. mortgage payment has four parts (PITI): principal, interest, property taxes and homeowners insurance. If you put down less than 20% on a conventional loan, private mortgage insurance (PMI) is usually added; FHA loans carry their own mortgage-insurance premium (MIP). Condos and many subdivisions add HOA dues. This calculator shows principal and interest only — add the rest for your true monthly housing cost.
How much house can I afford?
The 28/36 rule is a classic rule of thumb: keep your full housing payment (PITI) under 28% of gross monthly income and all debt payments under 36%. On a $100,000 salary that is $2,333 a month for housing, which at 6.75% over 30 years supports a loan of roughly $360,000 if all of it went to principal and interest — less once taxes and insurance are counted. Lenders set their own limits, and a payment that leaves little room for savings, childcare or a job change is a stretch even if it is approved.
Should I choose a 15-year or 30-year mortgage?
On the same $320,000 at 6.75%, the 15-year payment is $2,832 versus $2,076 — about 36% higher — but total interest falls from $427,185 to $189,708. Fifteen-year loans also usually carry a lower rate: Freddie Mac's survey for October 15, 2026 averaged 6.71% for 15-year loans against 7.40% for 30-year loans. Choose the 15-year if the payment fits comfortably; choose the 30-year if you want flexibility, and make extra principal payments when you can — that gets you much of the interest saving without the obligation.
What interest rate will I actually get?
Your rate depends on your credit score, down payment size, loan type (conventional, FHA, VA, jumbo), loan term, property type, and whether you pay discount points, on top of the day's market rates. Get Loan Estimates from more than one lender on the same day and compare the APR, which includes lender fees, not just the rate.
What is PMI and how do I avoid it?
Private mortgage insurance protects the lender if you default. On conventional loans it is usually required with less than 20% down, and the premium appears on your Loan Estimate. Avoid it with 20% down, or remove it later: you can ask to cancel it when your balance reaches 80% of the home's original value, and the servicer must end it automatically when the balance is scheduled to reach 78% (or at the loan's midpoint), if you are current on payments.
What is the difference between interest rate and APR?
The interest rate is what you pay on the balance. The APR (annual percentage rate) also folds in lender fees, points and some closing costs, expressed as a yearly rate — so it is usually higher than the rate and is the better number for comparing offers. This calculator uses the plain interest rate, because that is what determines the monthly payment.
Does paying extra on my mortgage really help?
Yes, and more than most people expect. Every extra dollar goes straight to principal, so it stops accruing interest for the remaining life of the loan. An extra $200 a month on a $320,000, 6.75%, 30-year loan cuts the payoff to 23 years 4 months and saves about $112,000 in interest. Make sure extra payments are applied to principal, not to next month's payment, and confirm there is no prepayment penalty.
What are closing costs on a mortgage?
Closing costs are the fees to originate and record the loan — appraisal, title insurance, lender origination fees, prepaid taxes and insurance, recording fees. Your Loan Estimate lists them, and the Closing Disclosure shows the final figures. They are paid at closing, separate from the down payment. Sellers sometimes agree to pay part of them ("seller concessions"), and some lenders offer lender credits that reduce closing costs in exchange for a higher rate.
Can I use this calculator for an adjustable-rate mortgage (ARM)?
Only for the fixed period. Enter the introductory rate and the full term to see the starting payment. When the loan adjusts, the payment is recalculated on the remaining balance, the new rate and the remaining term — so run a second calculation with the balance at the adjustment date (from your loan statement or the lender's projected schedule) as the price, a down payment of 0, the higher rate, and the years left.
Why is my first payment almost all interest?
Because interest is charged on the outstanding balance, and at the start the balance is the whole loan. On $320,000 at 6.75%, month one is $1,800 of interest and only $275.51 of principal. As the balance shrinks the split shifts, but slowly: on a 30-year schedule it takes 259 payments — 21 years and 7 months — to repay half the loan.