Mortgage Comparison Calculator

What this Mortgage Comparison Calculator does

This English-language mortgage comparison calculator lets you place two fixed-rate loan scenarios next to each other and see exactly where the numbers diverge. Enter a home price, down payment, term, APR, discount points, and closing costs for each offer, and the tool instantly returns the monthly payment, total interest paid, total cost over the full term, and upfront cash required — for both scenarios simultaneously. The column you care most about is the break-even month: the point at which the scenario with higher upfront costs (usually the one with discount points or lower APR) starts costing less in cumulative payments than the cheaper-upfront alternative. Most online mortgage comparison tools force you to run one scenario, write it down, and run another — leaving the mental math to you. This tool keeps both on screen at once. Whether you are comparing two lender quotes in New York, deciding between a 15-year and 30-year term, or evaluating whether paying points makes sense given your expected stay, the answers are immediate. 100% client-side — your data never leaves your browser. No uploads, no tracking, no server logs.

Features

• True side-by-side layout. Both scenarios render in parallel columns so you can compare mortgage quotes without toggling screens or copying numbers into a spreadsheet.
• Break-even month calculation. When one scenario costs more upfront but less per month, the calculator identifies the exact month at which cumulative savings offset the higher initial spend — critical for deciding whether to buy down your rate.
• Discount points modeled correctly. Each point equals 1% of the loan amount paid at closing. Enter the points and adjust the APR yourself to match the lender's buy-down quote; the tool handles the upfront cost and amortization math.
• Lifetime and monthly cost deltas. Three difference rows — monthly, lifetime, and upfront — show the magnitude of each gap so you can weigh short-term cash flow against long-term savings at a glance.
• 15-year vs 30-year ready. Change the term field in each scenario independently. The calculator handles any whole-year term, making the classic 15 vs 30 comparison as easy as flipping a single input.
• No account, no server. All arithmetic runs in your browser using standard amortization formulas. Nothing is sent to a server, stored in a database, or tied to an account. Close the tab and the data is gone.

How to use the Mortgage Comparison Calculator

Fill in both columns and results update instantly. You do not need to click a Calculate button.

1. Enter Scenario A (your baseline). Type the home price, down payment, loan term in years, and APR for your first offer. If the lender charges closing costs, enter them in the closing costs field.
2. Enter Scenario B (the alternative). Repeat for the second offer. A common comparison: Scenario A is a 30-year at 7.00% with zero points, Scenario B is the same loan at 6.75% after paying 1 discount point (1% of loan amount upfront).
3. Add discount points if applicable. If your lender quoted a rate reduction for paying points, enter the number of points (e.g. 1 or 0.5) and manually lower the APR field to the bought-down rate the lender provided.
4. Read the break-even month. If Scenario B has lower monthly payments but higher upfront costs, the break-even row tells you when B becomes the cheaper cumulative choice. If you plan to move or refinance before that month, A is the better deal.
5. Check the difference rows. The monthly and lifetime difference rows quantify the gap in plain dollar terms. For deeper modeling of what you might earn by investing the upfront difference instead, the [compound interest calculator](/en/compound-interest-calculator/) can help.

Common use cases

• Comparing two lender quotes. You received a Loan Estimate from two lenders on the same property. One has a lower APR but higher closing costs. Enter both into Scenario A and B to find out which is cheaper over your expected hold period — and at what month B's lower rate recoups its closing premium.
• Deciding whether to buy discount points. Your lender offers 6.75% with 1 point or 7.00% with zero points on a $400,000 loan. Enter both structures and check the break-even month. If you plan to stay more than that many months, paying the point saves money. If you expect to sell or refinance sooner, skip the points.
• 15-year vs 30-year mortgage. Set both scenarios to the same price and down payment, then set Scenario A to 30 years and Scenario B to 15 years with its (typically lower) APR. The lifetime cost difference is often striking — but so is the monthly payment difference. This comparison tells you exactly what the shorter term costs you each month and saves you over the life of the loan. For broader return modeling you can pair this with the [Investment ROI Calculator](/en/investment-roi-calculator/).
• Modeling a larger down payment. You have extra savings and are considering putting 20% down instead of 10% to avoid PMI. Set the same loan terms with different down payment amounts. The upfront difference row shows the additional cash required; the monthly and lifetime rows show the savings. Note that PMI itself is not modeled here — factor its cost separately (typically 0.5–1.5% of loan value annually).
• Refinancing decision. Treat your current mortgage as Scenario A: enter the remaining balance as the 'home price' (with $0 down payment), your current term remaining, and your current APR. Enter the refi offer in Scenario B including the new closing costs. The break-even month tells you when the refi pays for itself — the [loan calculator](/en/loan-calculator/) can help you estimate your current remaining balance.

Frequently asked questions