Home and auto calculators

Principal and interest is the number lenders advertise. What actually leaves your account is PITI: principal, interest, taxes and insurance, plus HOA dues and mortgage insurance if your deposit was under 20%. Private mortgage insurance protects the lender, not you, and by law it comes off automatically once the loan falls to 78% of the original value.

Affordability is set by the monthly payment, not the price, which is why the same salary buys wildly different houses at different interest rates. Lenders cap the payment at a share of your gross income and count taxes, insurance and dues inside it. What a lender approves is a ceiling, not a recommendation: it takes no account of childcare, retirement saving, or wanting to eat out.

Buying loads its costs at the front, in the deposit and the closing costs, and pays them back slowly through equity and appreciation. Renting is cheaper on day one and leaves cash free to invest, which is the part most comparisons forget. The honest question is not which is cheaper per month, it is how long you will stay: below the break-even point, transaction costs alone make buying the more expensive choice.

A car payment is the visible part of a much bigger figure. Depreciation is usually the single largest cost of owning a new car, running around 20% in the first year and roughly 15% a year after, and it never appears on a statement. Adding fuel, insurance and maintenance to the payment gives the number that actually belongs in a budget. The common guideline is to keep all car costs under 15% of take-home pay.

A refinance is a new loan, not an edit to the old one, so the clock starts again. That is the part the monthly saving hides: dropping a loan with 26 years left onto a fresh 30 year term can cut the payment and still cost more interest in total, because you are paying for four extra years. The break-even figure here only counts cash out of your pocket against cash saved each month. It ignores what that money could have earned elsewhere, assumes you keep the new loan to term, and cannot know whether you will move or refinance again first, which is what actually settles the question for most people. Rolling the costs in is not free either: they sit in the balance earning interest for the lender for the whole term.

Closing costs are three separate piles wearing one name. Lender charges pay for making the loan, title and government charges transfer the property, and prepaids and escrow are your own future bills collected early, so that last pile is not lost money, just money you need sooner than you expected. The estimate here is a model, not a quote. Under the federal disclosure rules the lender's own fees on the Loan Estimate cannot rise at all before closing, and the shoppable services cannot rise more than 10% in aggregate, but prepaids and escrow reserves sit outside both limits and move with your closing date. Nothing here covers a seller credit, a rate lock extension, an owner's title policy you choose to add, or repairs negotiated after the inspection.

Saving for a house is a race against a moving finish line, which is why a plan built on today's prices runs late. The target here grows with the market while your balance grows with your deposits, and the answer is the month the two lines cross. What it leaves out is everything about the market except the price: mortgage rates could fall while you save, which makes the same house cheaper to own, or rise, which does the opposite and matters far more than the deposit. It also assumes you never miss a month, and that the savings rate holds for the whole period, which no bank promises.

A discount point is prepaid interest: you hand over 1% of the loan and the lender shaves the rate, usually by something between an eighth and a quarter of a percent. Whether that is a good trade is entirely a question of how long the loan lives. Almost no 30 year mortgage lasts 30 years, because people move or refinance, and the day you do either, the unused half of that payment is gone. This compares both versions over the same number of months, counting the balance left at the end so the faster paydown on the lower rate is not ignored. It does not discount future dollars back to today, and it ignores what the cash could have earned invested instead, both of which push the honest break-even out a little further than the figure shown.

Lenders do not lend against your equity, they lend up to a share of the home's value and subtract every loan already secured on it. That share, the combined loan-to-value limit, is usually 80% to 85%, which is why a house with plenty of equity can still support a small line. The value here is your estimate; the lender will order an appraisal and use that instead, and a lower appraisal shrinks the line before anything else changes. The monthly figure below is interest only at today's rate, which is what most lines charge during the draw period. It is not the payment you will end up making: HELOC rates are variable, and when the draw period ends the balance converts to principal and interest over a shorter term, which is where the payment can double. This is your home as collateral, so the downside of getting it wrong is not a credit score.

Property tax is charged on assessed value, not on what you paid, and the two can be far apart. Some places assess at full market value, others at a fixed fraction of it, and an exemption comes off the assessed figure before the rate is applied rather than off the final bill. A mill is one dollar per thousand of assessed value, so 11 mills and 1.1% are the same rate written two ways. What this cannot tell you is the part that matters most over time: many states cap how fast an assessment can rise while you own the place, and a sale usually resets it, which is why the seller's tax bill is a poor guide to yours. Special assessments for schools, sewers or bonds sit outside the main rate too, and they arrive as separate lines on the real bill.

Equity grows from two directions at once, and they behave nothing alike. Appreciation is the market's opinion, it can stall for a decade or go backwards, and it is the larger number here only because the assumed rate is applied to the whole house rather than to your share of it. Principal paydown is the reliable half, and it starts almost invisibly: in the early years of a mortgage most of the payment is interest. Neither figure is money in hand. Selling costs take around 7% off the top, and none of this counts the roof, the taxes, the insurance or the maintenance you paid over the same period, so treat the equity line as a balance sheet, not a profit. The gain on a primary residence is usually tax free up to $250,000 single or $500,000 married, provided you lived there two of the last five years.

Two inputs on this page decide whether the deal works, and they are the two people get wrong. Vacancy is not zero. Tenants leave, and a month empty between them is 8% of the year gone before you count the cleaning and the listing. Maintenance is not the small number either: roofs, water heaters, HVAC and flooring all die on a schedule, and setting aside less than about 8% of rent means you are not saving for them, you are borrowing from them. A property that looks like it clears $300 a month on optimistic figures is usually a property that loses money. Beyond that, this model leaves out plenty: no rent growth, no appreciation, no depreciation deduction, no income tax, no capital expenditure reserve separate from maintenance, no leasing fee when a manager finds a new tenant, and no eviction. Cap rate ignores your mortgage entirely, which is the point of it: it describes the building, not the deal.

A lease is a rental with the depreciation priced in advance. You pay for the value the car loses over the term plus a finance charge, and hand it back. The finance charge is quoted as a money factor, a small decimal that hides how expensive it is: multiply it by 2400 and you have the APR. Dealers rarely volunteer that conversion. This runs the loan over the same number of months as the lease and credits you with the car at the end, less whatever is still owed on it, because the whole advantage of buying is that you own something afterwards. What is not modelled: mileage limits, which are typically 10,000 to 12,000 a year with charges around 25 cents for every mile over, wear and tear assessments at turn-in, the gap between the residual set on sticker price and the price you negotiated, and the fact that money spent now is worth more than money spent in three years. Sales tax on a lease is charged on the monthly payment in most states but on the full price in a few, which changes the answer.

Depreciation is the largest cost of owning a new car and the only one you never write a check for, which is exactly why it gets ignored. It is charged as a percentage of what the car is worth now rather than what you paid, so the curve is steep at the start and flattens out, and the money lost in year one alone is usually more than a year of fuel and insurance combined. The model here is a declining balance with a separate, larger drop in the first year. It cannot know your car: mileage well above average, a color nobody wants, a brand with weak resale or a model year facelift all move the real number, and used prices moved violently in both directions in the 2020s. Anything you spend on the car after buying it, from tires to a trade-in appraisal that comes in low, sits on top of this.