Mortgage guides

Plain-English explanations that pair with each calculator. Skim a guide, then run your own numbers.

How to calculate a mortgage payment
The standard fully-amortizing payment formula in plain English, with a worked example.
How amortization works
Why early payments are mostly interest and how the split shifts toward principal over time.
15-year vs. 30-year mortgage
When the lower lifetime interest of a 15-year beats the cash-flow flexibility of a 30-year.
How to pay off a mortgage early
Concrete strategies — extra principal, biweekly, lump sums, recast, refinance — and when each makes sense.
Mortgage recast vs. refinance
Both reduce your monthly payment, but they work very differently. Side-by-side comparison.
How PMI works
Why lenders require private mortgage insurance, what it costs, and how to get it removed.
How much house can I afford?
How DTI ratios, down payment, and reserves combine to set your real budget — not just the lender's max.
APR vs. interest rate
APR includes fees, the interest rate doesn't. Why the gap matters when comparing loan offers.
Loan-to-value (LTV) ratio
How LTV controls PMI, refinance eligibility, and rate pricing — and how to lower it.
Mortgage recast vs. refinance — calculator comparison
Side-by-side cost, eligibility, and outcome comparison — and which calculator to open first.
Mortgage recast with a lump sum
How a lump-sum recast lowers your monthly payment, with worked numbers and the alternatives.
When is a mortgage recast worth it?
A decision checklist for whether a recast actually fits your situation.
Mortgage recast cost calculator
Common recast fees, minimum lump sums, and how the costs compare to a refinance.
PMI removal calculator guide
How to read a PMI removal estimate, and the original-value vs. current-appraisal caveat.
When does PMI go away?
The 80% borrower-request and 78% automatic-termination rules in plain English.
PMI removal with extra payments
How extra principal payments accelerate PMI cancellation, with a worked example.
Amortization schedule with extra payments
How extras change a month-by-month schedule, with a worked example and CSV-export workflow.
Biweekly mortgage payments
How biweekly payments work, the third-party-fee trap, and the simple monthly-extra equivalent.
Lump-sum mortgage payment calculator
How a one-time principal payment shortens the loan, with the recast alternative.