Refinance Calculator

Calculate mortgage refinance savings, break-even point, and lifetime cost comparison. Includes rate sensitivity, cash-out analysis, and balance projection.

About the Refinance Calculator

Refinancing replaces your existing mortgage with a new loan — ideally at a lower rate, better terms, or both. The fundamental decision comes down to simple math: will the monthly savings from a lower rate outweigh the closing costs of the new loan? The break-even point tells you exactly how many months of savings it takes to recoup those costs.

A good rule of thumb: if you can reduce your rate by 0.75-1.0% or more and plan to stay in the home beyond the break-even point, refinancing is typically worthwhile. But the details matter — extending your term resets the amortization clock, and closing costs (typically 2-5% of the loan) reduce net savings. Cash-out refinancing adds further complexity by increasing your loan balance.

This calculator performs a comprehensive side-by-side comparison: current vs. new payment, monthly and lifetime savings, break-even analysis, rate sensitivity showing how different rates affect the decision, and a 10-year balance comparison so you can see how equity builds under each scenario.

Why Use This Refinance Calculator?

Refinancing decisions involve multiple tradeoffs: lower rate vs. higher balance, shorter term vs. higher payment, closing costs vs. monthly savings. This calculator quantifies every dimension — break-even, lifetime savings, balance trajectory — so you can make a data-driven decision rather than guessing. Keep these notes focused on your operational context.

How to Use This Calculator

  1. Enter your current loan balance, rate, and remaining years.
  2. Input the proposed new rate and loan term.
  3. Add estimated closing costs (typically 2-5% of loan).
  4. If taking cash out, enter the cash-out amount.
  5. Review monthly savings and break-even period.
  6. Check the verdict box for a quick recommendation.
  7. Use the rate sensitivity table to negotiate with lenders.

Formula

Monthly Savings = Current Payment − New Payment. Break-Even = Closing Costs / Monthly Savings (months). Lifetime Savings = (Current Total Cost) − (New Total Cost). New Loan Balance = Current Balance + Closing Costs + Cash-Out.

Example Calculation

Result: Monthly savings: $429 — Break-even: 14 months — Lifetime savings: $72,980

Refinancing from 7.0% to 5.5% saves $429/month. With $6,000 in closing costs, break-even is reached in just 14 months. Over the full loan life, total savings are $72,980. The verdict: clearly favorable if you plan to stay in the home beyond 14 months.

Tips & Best Practices

Practical Guidance

Use consistent units, verify assumptions, and document conversion standards for repeatable outcomes.

Common Pitfalls

Most mistakes come from mixed standards, rounding too early, or misread labels. Recheck final values before use. ## Practical Notes

Use this for repeatability, keep assumptions explicit. ## Practical Notes

Track units and conversion paths before applying the result. ## Practical Notes

Use this note as a quick practical validation checkpoint. ## Practical Notes

Keep this guidance aligned to expected inputs. ## Practical Notes

Use as a sanity check against edge-case outputs. ## Practical Notes

Capture likely mistakes before publishing this value. ## Practical Notes

Document expected ranges when sharing results.

Frequently Asked Questions

When should I refinance my mortgage?

When the new rate is at least 0.75-1.0% lower than your current rate, the break-even period is shorter than your expected time in the home, and the lifetime savings exceed the closing costs. Also consider refinancing to switch from an ARM to a fixed rate, to remove PMI, or to shorten the term.

What are typical refinance closing costs?

Closing costs typically range from 2-5% of the loan amount. For a $300K loan, expect $6K-$15K. This includes appraisal ($300-600), title insurance, origination fees, credit report, recording fees, and other charges. Some lenders offer "no-cost" refinancing by rolling costs into the rate.

Will refinancing restart my 30-year clock?

If you refinance into a new 30-year loan, yes — the amortization resets. This means more total interest even at a lower rate. To avoid this, refinance into a shorter term (20 or 15 years) or continue making your old payment amount on the new loan to pay it off faster.

How does refinancing affect my credit score?

Refinancing causes a temporary credit score dip (5-10 points) from the hard inquiry and new account. Your score typically recovers within 3-6 months. If you apply to multiple lenders within a 14-45 day window, credit bureaus count it as a single inquiry for scoring purposes.

Should I do a cash-out refinance?

Only if the use of funds generates a return higher than the mortgage rate (e.g., debt consolidation from 20%+ credit cards) or is truly necessary (home repairs, education). Using home equity for discretionary spending is risky. The calculator shows the additional cost of cash-out versus a standard refinance.

How long does refinancing take?

Typically 30-45 days from application to closing. The process includes application, credit/income verification, appraisal, underwriting, and closing. Rate locks are usually available for 30-60 days. Some lenders offer streamlined refinancing (like FHA Streamline) that can close in 2-3 weeks.

Related Pages