PMI Calculator

What this calculator does

This PMI calculator works out what private mortgage insurance costs you each month and when it stops. Enter the home price, your down payment, the interest rate, and the PMI rate your lender quoted, and it returns your current loan-to-value, the monthly premium, and the point at which the balance falls to 80 percent of value.

The table below tracks the loan year by year: the outstanding balance, the LTV that balance implies, and the PMI you pay that year. Adding those annual figures gives you the total cost of the insurance across its life — the number that actually matters when you are deciding between a smaller down payment now and a larger one later.

When to use it

The first use is at the offer stage, when you are choosing a down payment. Running five, ten, fifteen, and twenty percent shows both the monthly premium and how many years you would carry it, which converts an abstract preference for 20 percent into a dollar figure you can weigh against rent and rising prices.

The second use comes years later, when you suspect you are close to cancellation. The LTV column tells you which year your balance crosses 80 percent so you can send the request rather than waiting for the automatic 78 percent trigger, which typically arrives several months later. It is also the right tool before making a lump-sum principal payment, since removing PMI early is a saving on top of the interest saved.

Understanding the inputs

Home price should be the purchase price, because that is the figure PMI cancellation thresholds are measured against — not a later appraised value. Down payment is entered as a percentage; the meaningful range runs from three percent up to twenty, above which PMI does not apply.

PMI rate is the annual premium as a percentage of the loan amount, and it is quoted on your Loan Estimate. If you do not have a quote, 0.5 to 0.7 percent is typical for good credit around ten percent down, while a score in the low 600s at three percent down can reach 1.2 percent or more. The interest rate input drives how fast the balance falls, which is what sets the cancellation date.

How is this calculated?

Monthly PMI = (Loan Amount × PMI Rate) / 12. PMI removed when LTV reaches 80% (US). LTV = Loan Amount / Home Value × 100.

A worked example

Consider a $380,000 home with ten percent down, so a $38,000 down payment and a $342,000 loan at 6.5 percent over 30 years, with PMI quoted at 0.55 percent. The monthly premium is about $157, on top of a principal and interest payment of roughly $2,162.

The balance reaches 80 percent of the original price — $304,000 — in month 95, or just under eight years, at which point you can request cancellation. Total PMI paid over that period is around $14,900. Add $200 a month to principal and you cross the same threshold roughly two years sooner, saving close to $3,700 of premiums in addition to the interest that extra principal removes.

Limitations and assumptions

This models borrower-paid monthly PMI on a conventional loan. It does not cover single-premium PMI paid upfront, lender-paid PMI folded into the rate, or FHA mortgage insurance, which has different rules and on most loans never cancels at all. It also assumes a fixed rate and payments exactly on schedule.

Cancellation timing is based on the original purchase price, which is the legal standard, so appreciation is not modeled — some servicers will accept a new appraisal to cancel early, but that is at their discretion and costs a few hundred dollars. The PMI rate itself is set by the insurer based on your credit file, so treat any figure you have not been quoted as an estimate. Your Loan Estimate carries the real number.