Mortgage Refinance Calculator
Determine if refinancing your mortgage makes financial sense by comparing your current and new loan terms.
Your estimated monthly mortgage payment is $1,896 for a $300,000 loan at 6.5% over 30 years.
Why This Calculation Matters
The Mortgage Refinance Calculator helps you make better mortgages decisions by putting the math directly in front of you. Instead of relying on averages or guesswork, plug in your own numbers and see how the key inputs, rate, term, amount, and timing, interact. Small changes to any one of them can have outsized effects over years or decades.
How to Use This Calculator
- Enter your values in the input fields, each one has a label and help text explaining what to type.
- Results appear instantly as you type; there's no "calculate" button to press.
- Change any input to compare scenarios side by side.
All math happens in your browser. Nothing you type is sent to a server, saved, or shared.
Key Inputs to Get Right
The most important numbers are usually the interest rate and the time horizon. Over years or decades, small rate differences compound into large dollar differences, so it's worth sanity-checking the rate against current market data before acting on any result.
When Should You Refinance?
Refinancing replaces your current mortgage with a new one, ideally at a lower interest rate. The general rule is that refinancing makes sense if you can reduce your rate by at least 0.5-1%.
Break-Even Analysis
Calculate how many months of savings it takes to recoup closing costs. If you plan to stay in the home longer than the break-even point, refinancing likely makes sense.
When to Use This Calculator
- Model scenarios before making a major financial decision involving mortgages.
- Compare different inputs side by side to see how rate, term, or amount changes your outcome.
- Sanity-check numbers a lender, advisor, or spreadsheet has given you.
- Build a realistic financial plan grounded in your actual numbers, not averages.
Limitations & Common Mistakes
- Results are estimates, actual terms depend on credit, lender policy, taxes, and fees not captured here.
- Rates and prices change daily; recompute with current numbers before signing documents.
- Does not constitute financial advice. For major decisions, consult a licensed advisor.
Frequently Asked Questions
When does refinancing make sense?
Refinancing typically makes sense when you can lower your interest rate by at least 0.5%, plan to stay in the home long enough to recoup closing costs, or need to switch from an adjustable to a fixed rate.
What are typical refinance closing costs?
Refinance closing costs typically range from 2-5% of the loan amount. This includes appraisal fees, title insurance, origination fees, and other charges. Some lenders offer no-closing-cost refinances with a slightly higher rate.
How accurate is the Mortgage Refinance Calculator?
Results use standard financial formulas and are a reliable planning estimate. Exact numbers depend on your lender's rates, fees, and underwriting, always verify with a loan estimate before signing.
Does this account for taxes, insurance, and fees?
The calculator shows the core figure by default. Taxes, insurance, PMI, HOA dues, and closing costs can materially change your monthly cost, factor them in when budgeting.
Is this calculator free to use?
Yes. The Mortgage Refinance Calculator is free, requires no signup, and runs entirely in your browser, your inputs are never sent to a server.
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