Compare Two Mortgages Calculator

A loan comparison is not a contest between two headline interest rates. It is a side-by-side estimate of what two repayment plans cost over the period you expect to keep them. This calculator starts with one loan amount, then lets you describe Option A and Option B using separate rates, terms, and fees. It reports each monthly payment, estimates each option's cost through the selected horizon, and names the cheaper option when the totals differ.

That framing is useful when one offer has a lower rate but higher upfront charges, when one term is shorter, or when you expect to sell, refinance, or repay before the scheduled end. The result is an estimate for comparison, not a promise about a lender's quote. Keep the loan amount, rate convention, fee treatment, and comparison period consistent so that the difference reflects the options rather than mismatched assumptions.

Enter the amount being borrowed in Loan amount. This is the principal used for both options; it is not a purchase price unless the amount you type is already the financed amount. Enter the period you want to compare in Compare through, measured in years. A seven-year horizon asks the calculator to compare the estimated cost accumulated through year seven, even if either loan has a much longer scheduled term.

Opportunity-cost rate is an optional annual percentage used to discount future payments and the remaining balance into a present-value comparison. At zero percent, future dollars are not discounted. A positive value gives less present weight to cash flows farther in the future. It does not change either loan's contractual interest rate or monthly payment; it changes how the calculator values timing when it compares costs.

Because the component accepts non-negative numeric fields and displays dollars, years, and percentages explicitly, use a rate such as 6.1 rather than 0.061, a term such as 30 rather than 360, and fees as a dollar amount such as 5,500 rather than a percentage.

Each option has three inputs: Interest rate, Term, and Fees. Interest rate is the annual percentage applied by the payment calculation. Term is the scheduled repayment length in years. Fees are the upfront costs you want included in the comparison. If an offer has points, origination charges, or other known costs that belong in your decision, include them in the same fee field; do not include a fee in one option and omit the equivalent cost from the other merely because it has a different label.

The calculator does not ask you to enter a separate payment, balance, tax, insurance, or cash-flow schedule. It derives the monthly payment from the common loan amount, the option's rate, and the option's term. Consequently, the two options are most fairly compared when they describe the same kind of amortizing loan and the fee figures are defined on the same basis. Variable-rate changes, irregular payments, penalties, and other product features require a separate review outside this screen.

Suppose the shared loan amount is $320,000 and the comparison horizon is seven years. Enter 6.5% for Option A, a 30-year term, and $2,000 in fees. Enter 6.1% for Option B, the same 30-year term, and $5,500 in fees. The lower rate in Option B should reduce its monthly payment, while the additional $3,500 fee works in the opposite direction. The calculator's result list shows the monthly payment for each option and an estimated cost through seven years for each option.

Read the result rather than deciding from the rate alone. If Option B's lower payment and lower discounted cost outweigh its extra fee by year seven, it is shown as cheaper and the result card displays the estimated saving through the selected horizon. If the fee difference still dominates, Option A is cheaper. The exact break-even point depends on the component's amortization and present-value calculation, so change Compare through to test a shorter or longer expected holding period instead of assuming that a lower rate always wins.

Monthly payment is the recurring payment implied by that option's principal, annual rate, and term. It is a cash-flow measure, not the full cost of borrowing. A longer term can produce a smaller monthly payment while leaving more balance outstanding later. A shorter term can show a larger monthly payment while reducing the balance faster. Compare payments to your budget, but use the horizon cost to compare the offers themselves.

Est. cost through seven years, or the equivalent label for your selected horizon, is the calculator's estimate of each option's cost through that point. It incorporates the entered fees and accounts for the remaining balance, rather than pretending that every payment made is pure expense. With a positive Opportunity-cost rate, the calculation also recognizes that a dollar paid later is not valued the same as a dollar paid today. The number is therefore best read as a decision metric under your assumptions, not as the total of every scheduled payment over the full term.

The Result card says either Option A is cheaper, Option B is cheaper, or Both options cost the same. When one option is cheaper, Estimated saving states the difference through the selected horizon, including fees and remaining balance. Treat a small difference as sensitive to rounding, fee changes, timing, and assumptions; it may not justify operational inconvenience or a product feature you value.

Start with a neutral test: keep the loan amount, horizon, and opportunity-cost rate fixed while entering each offer's actual rate, term, and fees. Then change only one assumption at a time. Set both fees equal to see the pure effect of rate and term. Set both rates equal to see how much the upfront fee difference matters. Finally, vary the horizon from the expected payoff date to the expected hold date. A short horizon favors avoiding large upfront charges; a long horizon gives a lower rate more time to offset them.

A second useful test changes the term for one option. For example, Option A can represent a 30-year schedule while Option B represents a 20-year schedule. The payment comparison will then include a cash-flow trade-off, and the horizon cost will reflect the different remaining balances. That is a meaningful comparison only if you can afford the larger required payment and are genuinely considering the different schedule. Do not call the smaller payment the cheaper option without reading the horizon result.

The most common mistake is entering an APR, promotional rate, or rate after an assumed discount in one field while entering a plain note rate in the other. Define what each number represents before comparing. Another mistake is putting total scheduled interest into Fees. Fees should be upfront charges; the calculator derives payment-related cost from the rate and term. Also avoid using a seven-year horizon to answer a question about the full scheduled life, or using a full-term horizon when you already know you will repay much sooner.

Do not use the result as a substitute for checking whether both offers have the same repayment structure. Confirm whether fees are paid at closing, financed, refundable, or contingent, and check any terms that the component does not model. When the comparison is close, run a range of plausible fees, rates, and horizons and record which assumptions change the winner.

After comparing two loan offers, the natural sibling use case is a refinance calculator: use it when one option is an existing loan and the other is a new loan, and you need to focus on replacing the current balance and recovering refinance costs. If your question is instead how a single loan's balance changes payment by payment, move to an amortization schedule calculator.