Every Mortgage Calculator You'll Ever Need.

The plain-English version of the biggest loan most people will ever take on.

A mortgage is a loan used to buy real estate, secured by the property itself. That last part matters: because the home is collateral, lenders can offer far lower interest rates than on a credit card or personal loan — if you stop paying, they can take the property back through foreclosure. Every mortgage has three core pieces that drive your monthly payment: the loan amount (how much you borrow), the interest rate (what the lender charges you each year to borrow it), and the term (how many years you have to repay). Change any one of those three and your payment moves — which is exactly why a small rate change can mean hundreds of dollars a month. Most mortgages in the United States are amortized, meaning each monthly payment covers both a slice of interest and a slice of principal. Early in the loan, almost all of your payment is interest; near the end, almost all of it is principal. That shift is what builds your equity over time. You can see it play out payment by payment with the amortization schedule calculator.

The 28/36 rule, debt-to-income ratios, and why "approved" does not mean "affordable."

Lenders use two ratios to size up how much debt you can safely carry. The front-end ratio compares your monthly housing payment (principal, interest, taxes, and insurance — PITI) to your gross monthly income. The back-end ratio compares all of your monthly debts combined to your gross income. A long-standing guideline called the 28/36 rule says housing should stay under 28% of gross income and total debt under 36%. Those ratios are the lender's view of risk, not your view of comfort. A lender might approve you for a payment that eats up 36% of your gross income, but your take-home pay is lower than your gross, and you still have to cover groceries, utilities, transportation, childcare, and savings. Many buyers who borrow the maximum end up house-rich and cash-poor. The affordability calculator applies the 28/36 rule to your income and debts to estimate a healthy maximum home price. Treat that number as a ceiling, not a target — the most comfortable buyers usually borrow well below it.

You do not need a fifth of the home price in cash — but there is a trade-off.

The idea that you must put 20% down is one of the most stubborn myths in home buying. It comes from private mortgage insurance (PMI): conventional loans with less than 20% down require PMI, which adds to your monthly payment. So 20% down is a way to avoid PMI, not a legal requirement. Plenty of loan programs allow far less. FHA loans — backed by the Federal Housing Administration — accept as little as 3.5% down for qualifying buyers. VA loans for eligible service members and veterans, and USDA loans for eligible rural properties, can require zero down. Conventional loans often start at 3% for first-time buyers. The trade-off is real, though. A smaller down payment means a larger loan, a higher monthly payment, more interest paid over the life of the loan, and usually some form of mortgage insurance on top. Use the down payment calculator to see exactly how different down payment amounts change your loan size, payment, and total interest — then balance that against keeping enough cash in reserve for closing costs, moving, and emergencies.

Predictable payments versus a lower starting rate that can move later.

A fixed-rate mortgage locks in your interest rate for the entire term. Your principal-and-interest payment never changes, which makes budgeting simple and protects you if rates rise. The trade-off is that fixed rates usually start a little higher than the introductory rate on an adjustable mortgage. An adjustable-rate mortgage (ARM) has a rate that stays fixed for an introductory period — often 5, 7, or 10 years — and then adjusts periodically based on a market index plus a margin. ARMs usually offer a lower starting rate, which can help if you plan to sell or refinance before the first adjustment. The risk is that after the fixed period, your rate and payment can rise, sometimes sharply. If you expect to move within the introductory period and want the lowest possible starting payment, an ARM can make sense. If you plan to stay long-term, value predictability, or worry about rates rising, a fixed-rate mortgage is usually the safer call. The ARM calculator lets you model a worst-case payment so you know what you are signing up for.

The fees on top of your down payment — and why they catch buyers off guard.

Closing costs are the fees and expenses paid to finalize a home purchase, separate from and in addition to your down payment. They typically run 2% to 5% of the loan amount, and because they come due at the same time as your down payment, they catch many first-time buyers by surprise. Closing costs fall into a few buckets. Lender fees include origination, application, and underwriting charges. Title fees cover a title search and title insurance, which protects against past ownership disputes. Government fees include recording the deed and any transfer taxes. Prepaids are upfront payments for future property taxes and homeowners insurance, held in an escrow account. Some costs are negotiable — you can ask the lender to reduce certain fees or request seller credits during negotiations to lower your out-of-pocket total. Cash to close is the final number: your down payment plus closing costs plus prepaids, minus any earnest money you already paid and any credits. You will see this figure on your Closing Disclosure a few days before closing. Review it carefully — it is the check you write to get the keys.

Small changes to your payment schedule can save tens of thousands over a loan.

Because mortgage interest is charged on your remaining balance, anything that reduces the balance faster also reduces the interest you pay. Three approaches compound quietly over the life of the loan. First, making extra principal payments. Even a modest extra amount each month — $50 to $100 — is applied directly to principal, shrinking the balance faster and lowering every future interest charge. On a 30-year loan, this can knock years off the term. Just confirm with your lender that extra payments apply to principal, not future interest. Second, a biweekly payment plan. Instead of one monthly payment, you pay half every two weeks. Because there are 52 weeks in a year, that works out to 26 half-payments — the equivalent of 13 full monthly payments instead of 12. The extra payment each year goes to principal. You can usually set this up directly with your lender and should avoid paid third-party services that charge for it. Third, a shorter loan term. A 15-year mortgage has a higher monthly payment than a 30-year, but the rate is usually lower and you pay interest for half as long. The total interest difference between a 15- and 30-year loan on the same amount is often enormous. The extra payment and early payoff calculators show the exact numbers for your situation.