Tools organized by decision workflow

The workflows above are ordered deliberately, because running these tools out of sequence is how people end up with a number that looks precise and is still wrong. Each step feeds the next one.

If you are early and just want a budget, start with the affordability calculator. It converts income, down payment, and a rate assumption into a payment and a loan size. Enter taxes, insurance, and HOA as real numbers rather than leaving them at a default, because in high-tax counties those lines can add several hundred dollars a month and change which houses are actually in range.

If a lender has already told you a number you do not trust, go to the DTI calculator. Underwriting approves based on ratios, not on what feels comfortable, and the maximum approval and the payment you want to live with are frequently different numbers. Seeing both before you start touring saves a lot of disappointment.

If you are still deciding whether to buy at all, the rent vs buy calculator is the right starting point. It is the only tool here built around a time horizon, which is the variable that actually decides the question. Buying usually loses over two years and usually wins over ten, and the crossover point depends on your rent, your closing costs, and local appreciation.

If you already own and rates have moved, use the refinance workspace. Focus on break-even timing against how long you plan to stay, not on the monthly savings figure alone.

If you are selling, the seller decision path asks what you are optimizing for and routes you to the net sheet and offer comparison in the right order.

Every calculator on this site is only as good as its inputs, and three inputs cause most of the bad answers.

The rate you assume. The headline rate in the news is a survey average for a borrower with strong credit and a conventional conforming loan, often with points paid. Your quote will differ. Use the market page for direction, then run your math at a rate a bit above the headline so a realistic quote does not break your plan.

Everything that is not principal and interest. Property tax, homeowners insurance, mortgage insurance, and HOA dues routinely add 25 to 40 percent on top of the loan payment. A calculator that shows only principal and interest is showing you a number you will never pay. Our walkthrough of the full payment is in PITI and escrow basics.

Your time horizon. Rent vs buy, refinance break-even, and ARM decisions all hinge on how long you stay. Guessing optimistically here is the single most common way these calculations go wrong.

Results are planning estimates, not quotes or credit decisions. Rateshive is not a lender. Actual terms come from a licensed lender after a full application.

The calculators will disagree with each other if you feed them different assumptions. Use one rate, one tax figure, and one insurance quote across the set. Pull the rate direction from the market page, then add a small cushion so a real Loan Estimate does not break the plan. Pull the tax from the parcel, not from a national default. Pull the insurance from a current quote on the address.

Buyers usually need three passes. Affordability sets a ceiling. Debt-to-income shows what underwriting will count, which can be higher than the payment you want. Offer comparison is for the week you have two real estimates, same lock, same points. Rent versus buy is the pass you run before any of that if you are not sure you will stay long enough for the closing costs to earn their keep.

Sellers run the decision path first so you know whether you are optimizing cash, speed, or certainty. Then the net sheet, with a written payoff rather than the statement balance. Then offer comparison once the envelopes exist. Refinance is its own path: costs divided by savings, compared with the years you will stay, and with the cost of stretching the term. The long versions of each of those arguments live in Learn. The tools are the arithmetic. The guides are the judgment about which arithmetic matters.

If two tools disagree, check the inputs before you assume one of them is broken. A mortgage calculator that omits taxes will look cheaper than a budget planner that includes them. A refinance break-even that ignores a restarted 30-year term will look kinder than the interest you actually pay. Match the rate, the term, and the fees, then read the guide linked from that workflow if the verdict still feels off. The sourcing behind any benchmark you typed in is on the methodology page.