Mortgage Refinance Calculator
See how much refinancing could save you.
Result
How it is calculated
The tool compares the monthly payment of the loan at the old rate and at the new rate over the same term. For each rate the payment is PMT = B × r / (1 − (1 + r)−n), where B is the remaining balance, r is the annual rate divided by 12 and by 100, and n is the term in months. The saving is the old payment minus the new one. It uses one term for both loans, so shortening or extending the term changes the picture. Closing costs, fees and the loan interest paid over the whole life are not included, so a lower payment is not automatically a better deal.
Worked example
Balance $250,000, old rate 6.5%, new rate 5.25%, 360 months. Old payment: r = 0.065 / 12 = 0.005417, which gives $1,580.17. New payment: r = 0.004375, which gives $1,380.51. Monthly savings = 1,580.17 − 1,380.51 = $199.66. Divide the refinancing costs by 199.66 to see how many months it takes to recover them.
Common mistakes
- Entering the rate as a monthly percentage instead of the annual rate; the tool divides by 12 itself.
- Entering the original loan amount instead of the remaining balance.
- Entering the years where months are expected; the term is in months (30 years = 360).
- Ignoring closing costs and a restarted term, which can cancel out a lower monthly payment.
Sources
- A Consumer's Guide to Mortgage Refinancings — Board of Governors of the Federal Reserve System
- 8.3 Loan Amortization (Principles of Finance) — OpenStax, Rice University
About this calculator
This calculator compares your current mortgage payment against a new one at a different interest rate over the same term and balance, to show the monthly savings. Closing costs, fees and the interest paid over the life of the loan are not included, so it does not give a break-even point.
Homeowners use it whenever mortgage rates drop or their credit improves, to see how much a lower rate cuts the monthly payment and then weigh that saving against closing costs and how much longer they plan to stay in the home, rather than assuming a lower rate automatically means a better deal.
Was this helpful?
You can pick up to 3 reactions.
Popular calculators
Loan Calculator
Monthly payment, total interest and full amortization schedule.
Percentage Calculator
Percent change, percent of, and ratio calculations.
Discount Calculator
Calculate final price, savings, and discount amount.
BMI Calculator
Body mass index from height and weight (metric or imperial).
Age Calculator
Compute your exact age in years, months and days from a birth date.
Compound Interest Calculator
Calculate the final amount and interest earned with compounding.
All Calculators
- Loan Calculator
- Profit Calculator
- Discount Calculator
- BMI Calculator
- Percentage Calculator
- Ideal Weight Calculator
- Age Calculator
- Pregnancy Due Date Calculator
- Compound Interest Calculator
- BMR Calculator (Basal Metabolic Rate)
- Tip Calculator
- Fuel Cost Calculator
- Date Difference Calculator
- Sleep Cycle Calculator
- Daily Water Intake Calculator
- Simple Interest Calculator
- Heart Rate Zones Calculator
- Running Pace Calculator
- Pet Age Calculator
- Calories Burned Calculator
- Macro Calculator
- TDEE Calculator (Total Daily Energy Expenditure)
- Waist-to-Hip Ratio Calculator
- Honor Roll Calculator
- One Rep Max (1RM) Calculator
- Ovulation Calculator
- Electricity Cost Calculator
- Unit Price Calculator
- Savings Goal Calculator
- Break-Even Point Calculator
- Paint Calculator
- Course Grade Average Calculator
- Business Days Calculator
- Time Duration Calculator
- Fuel Economy Calculator
- Temperature Converter
- Tile Calculator
- Aspect Ratio Calculator
- Roman Numeral Converter
- Goal Weight Timeline Calculator
- Salary Converter (Hourly to Annual)
- Credit Card Validator (Luhn)
- Body Surface Area (BSA) Calculator
- Feels-Like Temperature Calculator
- Ohm’s Law Calculator
- PPI (Pixel Density) Calculator
- Molar Mass Calculator
- Zodiac Sign Calculator (Western + Chinese)
- IBAN Validator
- Shoe Size Converter
- Country Info & Dialing Code Lookup
- Time Zone Difference (World Clock)
- CAGR (Compound Annual Growth Rate) Calculator
- Rule of 72 Calculator
- Blood Alcohol Content (BAC) Calculator
- Lean Body Mass (LBM) Calculator
- Pythagorean Theorem Calculator
- Speed Converter
- Download Time Calculator
- Date Calculator (Add/Subtract)
No calculators found
Comments (1)
The tool recomputes both payments from the balance and the single term you enter, so it assumes the new loan runs the same number of months as the old one. Enter the months you have left, not 360. Restarting a long term can shrink the monthly payment while raising the total interest you pay overall. It is plain annuity math, so taxes and insurance are not included. What closing costs are you weighing against the savings?