Compare lenders side-by-side, calculate your break-even point, and get a complete financial analysis — all in one place.
Basic: Compare lender rates and estimate monthly savings
Enter your existing mortgage details
Required field
Add one or more refinance offers to compare side-by-side
Your data stays in your browser — nothing is stored or transmitted.
Provide your original loan amount, current balance, interest rate, and remaining term.
Enter multiple lender quotes with their offered rates, terms, and closing costs.
Instantly see break-even points, total savings, and a clear recommendation for each offer.
A complete guide to what this calculator does, who built it, why it exists, and the math behind every number it produces.
About & Purpose
RefinanceCalculator.site is a free, server-side mortgage refinance analysis tool. Enter your current loan details and up to five lender quotes, and the calculator runs a complete side-by-side financial comparison — monthly savings, break-even timeline, total interest cost, and net lifetime savings for every option. First time here? The step-by-step guide walks through every input and result.
Built by Aesepus Technology, a software and web development company that builds free, practical tools for financial decisions. No sign-up required, no subscription, no hidden fees — ever. The calculator runs entirely server-side so your inputs are never stored or tracked.
Refinancing looks simple — get a lower rate, save money. But a lower rate doesn't always mean savings. Closing costs, your remaining term, and how long you plan to stay all affect the real outcome. Without proper math, you can end up paying more over the life of the loan even with a lower monthly payment. This tool does the full analysis before you walk into a lender's office. Not sure if your situation even calls for refinancing? Read real-world scenarios that cover common and complex situations.
To give every homeowner the same analytical clarity a financial advisor would provide — for free. The calculator answers one core question: "Given my specific situation, does refinancing make financial sense, and which lender offer is actually the best deal?" Once you have the numbers, the 10-step refinance guide shows you exactly how to act on them.
Key Features
The Formulas Explained
Monthly Payment (Amortization)
M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1]
P = loan principal · r = monthly interest rate (annual rate ÷ 12) · n = total number of monthly payments. This is the standard fixed-rate amortization formula used by every lender.
Break-Even Point
Break-Even Months = Closing Costs ÷ Monthly Savings
The number of months it takes for your monthly payment reduction to fully recover the upfront cost of refinancing. If you sell or move before this point, refinancing costs you money net of savings. See how this plays out in practice across 13 different homeowner situations in our real-world scenarios guide.
Total Interest Paid
Total Interest = (M × n) − P
The total amount paid to the lender above the principal over the full loan term. Comparing this figure across lenders — not just the monthly payment — reveals the true long-term cost of each offer.
Net Lifetime Savings
Net Savings = Interest Saved − Closing Costs
Interest Saved = (Current Total Interest) − (New Total Interest). Subtracting closing costs gives the real financial benefit of refinancing over the life of both loans. A positive result means refinancing is profitable.
Loan-to-Value Ratio (LTV)
LTV = (Loan Balance ÷ Home Value) × 100
Expressed as a percentage. Lenders use LTV to assess risk. An LTV above 80% typically requires Private Mortgage Insurance (PMI). Refinancing to an LTV ≤ 80% can eliminate PMI and reduce your total monthly cost.
PITI — Total Monthly Housing Cost
PITI = Principal + Interest + Taxes + Insurance
The complete monthly cost of homeownership beyond the bare mortgage payment. In Advanced Mode the calculator adds property taxes, homeowner's insurance, PMI, and HOA fees to give you a true cost comparison between your current loan and each refinance offer.
Discount Points Value
Points Break-Even = Point Cost ÷ Monthly Rate Savings
Each point costs 1% of the loan amount and typically reduces the rate by ~0.25%. The break-even tells you how many months until the lower rate recoups the cost of buying points. Only worth it if you stay past that point. Unfamiliar with any of these terms? The mortgage glossary has plain-English definitions for everything.
Run the numbers here, then use these guides to understand them, act on them, and make sure refinancing is right for your situation.
How to Use the Calculator
Step-by-step walkthrough of every input, result, and chart — Basic Mode through Advanced Mode.
Refinance Scenarios
13 real homeowner situations — rate drops, ARM resets, FHA escapes, divorce buyouts, and more.
The Refinance Process
A 10-step guide from evaluating your current loan through rate lock, underwriting, and closing.
Mortgage Glossary A–Z
Plain-English definitions for APR, break-even, LTV, PMI, closing costs, amortization, and more.
About This Tool
Built by Aesepus Technology — free, no sign-up, no tracking. Learn how the calculator works.