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Mortgage Comparison Calculator

Compare two mortgages — payment, total interest and total cost — to see which term and rate wins.

Related tools

All Buying tools →
Interest-Only Mortgage CalculatorShows the payment shock at the end of the interest-only period: the low payment while only interest is due, the higher one once the whole principal has to be repaid over the years that are left, and the exact size of the jump. Puts the lifetime interest side by side with a fully amortising loan of the same rate and term.PMI calculator (private mortgage insurance)Private mortgage insurance is charged when you put down less than 20%. From the price, down payment, term and rate the calculator finds your loan-to-value, estimates the annual PMI rate (or uses yours), and shows the monthly PMI, when it should drop off at 78% LTV, and the total PMI you'll pay until then.Reverse mortgage calculator (HECM estimate)Estimate how much a HECM reverse mortgage could provide. Based on the youngest borrower's age (62+), the home value (capped at the 2026 HECM limit of $1,249,125) and the expected interest rate, it approximates the principal limit factor, the gross principal limit, the mandatory payoff of any existing mortgage and the net amount available to you.ARM mortgage calculatorSee how an adjustable-rate mortgage could move. Enter the loan, the fixed introductory rate and how long it lasts (3/5/7/10 years), the term and the rate caps. The tool shows the initial payment, the maximum payment after the first adjustment (initial cap, bounded by the lifetime cap) and the worst-case payment at the lifetime ceiling — with an optional fixed-rate comparison.Mortgage Overpayment CalculatorSee how much time and interest you save by paying extra on your mortgage each month.Mortgage points calculatorCompute the upfront cost of mortgage discount points on a loan.Mortgage recast calculatorA recast re-amortises your mortgage after a lump-sum principal payment, keeping the same rate and remaining term but lowering the monthly payment. Enter your current balance, rate, original term, months already paid, the lump sum and any recast fee to see the new payment and the interest you save.Home Affordability CalculatorFind the maximum home price you can afford from your income, debts and down payment, using the 28/36 debt-to-income rules.

Mortgage Comparison Calculator works straight from this page — free, instant, nothing to install. Its place is under Buying; Interest-Only Mortgage Calculator and PMI calculator (private mortgage insurance) answer the questions closest to this one.

How to use it

  1. Open the tool — no signup or install needed.
  2. Enter your input or adjust the available options.
  3. Get your result instantly, then copy or download it.

Frequently asked questions

What does Mortgage Comparison Calculator do?

Compare two mortgages — payment, total interest and total cost — to see which term and rate wins.

When would I actually use this?

Before making an offer: what the bank will lend, what the purchase costs on top of the price, and how much deposit closes the gap.

What is the most common mistake?

Budgeting for the price and forgetting the acquisition costs. Notary fees, transfer duty and registration add between 2% and 15% depending on the country — enough to sink an offer.

How is Mortgage Comparison Calculator different from Interest-Only Mortgage Calculator?

They sit next to each other but answer different questions: Interest-Only Mortgage Calculator is the one to open when you need it to shows the payment shock at the end of the interest-only period: the low payment while only interest is due, the higher one once the whole principal has to be repaid over the years that are left, and the exact size of the jump. Puts the lifetime interest side by side with a fully amortising loan of the same rate and term. Pick whichever matches what you're starting from — both are free.

Is there a tool for the next step?

PMI calculator (private mortgage insurance) is the closest one after this: Private mortgage insurance is charged when you put down less than 20%. From the price, down payment, term and rate the calculator finds your loan-to-value, estimates the annual PMI rate (or uses yours), and shows the monthly PMI, when it should drop off at 78% LTV, and the total PMI you'll pay until then.

What else is worth having open alongside it?

Reverse mortgage calculator (HECM estimate) and ARM mortgage calculator — they come up in the same task often enough to be worth a second tab.

Where do the figures come from?

Fee scales and duty rates are published per country and per region, and they change with each finance act. Lending limits also depend on the bank's own policy, not only on the regulator's debt-to-income cap.

Further reading

All guides →
ComparisonComparing Two Mortgage Offers ProperlyThe rate is not the comparison. Over a five-year holding period the 6.25 percent offer with $2,000 of fees beats the 5.875 percent offer with $12,000 by $2,485.73; the crossover falls at month 80, not at the month 103 the simple payback suggests.ExplainerAdjustable-Rate Mortgages and the Caps That Bound ThemA 5.00 percent start with 2/2/5 caps can legally reach 10.00 percent and a payment of $2,484.14 — 54.3 percent above where it began. That worst case is computable before you sign, and it is the only number that should decide the choice.ExplainerMortgage Points: When Buying Down the Rate Actually PaysOne point on a $300,000 loan costs $3,000 and saves $47.93 a month. The naive break-even is 63 months; discounted at 4 percent it is 71. And the number that decides it is not either of those — it is how long you keep the loan.ExplainerWhat Is Loan-to-Value (LTV), and Which Bands Actually Change AnythingLoan divided by the lower of price and appraised value. The bands at 80, 90 and 95 percent are where pricing steps — and a valuation that comes in low moves you across one without you touching the deposit.ExplainerUK Stamp Duty Is a Slice Tax, Not a Slab TaxOnly the part of the price inside each band is taxed at that band's rate. On £450,000 that is £12,500 in England, £18,350 in Scotland and £14,250 in Wales — three separate taxes, and the old slab system's £5,000 cliff edges are gone.GuideWhen Refinancing a Mortgage Actually Pays: France, Germany, ItalyThe rule of thumb everyone repeats — one point of rate gap — is not a rule and gets the timing wrong. What decides it is how much interest you have not yet paid, and the three countries answer the cost side in three completely different ways. Here is the arithmetic, computed.