Mortgage Refinance & Loan Analyser

Model your mortgage refinance — compare payments, savings, and break-even timeline.

Current Loan Parameters
$0$2M
Where to find it: Your original loan documents, closing disclosure, or mortgage statement.
Typical US ranges (2026):
  • Conforming loan limit: $766,550 (most states) — loans above this are jumbo
  • High-cost area limit: up to $1,149,825 (e.g. NYC, LA, SF)
  • National median home loan: approx. $300,000–$400,000
Do not enter your current remaining balance here — use the original amount at origination.
1.0%15.0%
Where to find it: Mortgage statement, original Note, or your lender's online portal.
Historical context:
  • 2020–2021 historic lows: 2.65%–3.25% (30-yr fixed)
  • 2022–2023 rapid rise: 6.0%–8.0%
  • 2025–2026 range: approx. 6.0%–7.5% (30-yr fixed)
Enter your rate as a number (e.g. 6.5 for 6.5%). This is your note rate, not your APR.
Original loan term
yr
Or type any term (1–40 years)
0 yr30 yr
Why it matters: The further into a loan you are, the more your payments shift toward principal — refinancing resets this clock.
Rule of thumb:
  • 0–5 years paid: Most interest is still ahead — refinancing has the biggest potential impact
  • 5–15 years paid: Evaluate carefully — a new 30-yr loan restarts the amortisation curve
  • 15+ years paid: Consider a shorter new term (10–15 yr) to avoid paying more total interest
Use whole years. If you are mid-year, round down.
Refinance Parameters
What is a recast? You pay down a chunk of the balance at closing — the new loan is then calculated on the reduced amount, lowering your monthly payment further.
Best practice:
  • Use this if you have savings you want to deploy to reduce debt
  • Typical minimum lender recast: $5,000–$10,000
  • Leave at $0 if you are not making an additional payment at closing
Leave blank or zero if not applicable.
New loan amount (refi)
$—
Remaining balance minus recast amount +
When closing costs are financed, the closing % is applied to the pre-closing balance — the new loan total may be marginally understated (immaterial at typical closing cost rates).
1.0%15.0%
Where to get a rate: Request quotes from at least 3 lenders — rates vary by 0.5%+ between lenders for the same borrower profile.
2026 market benchmarks (30-yr fixed, good credit):
  • Conforming: approx. 6.0%–7.5%
  • Jumbo: approx. 6.25%–7.0%
  • FHA: approx. 5.75%–7.0%
  • 15-yr fixed: typically 0.5%–0.75% lower than 30-yr
General rule: A refinance is typically worth considering if your new rate is at least 0.5%–1.0% lower than your current rate, though break-even analysis matters more than the rate difference alone.
0%6%
What's included in closing costs:
  • Origination fee: 0.5%–1.5% of loan amount (lender charge for processing)
  • Appraisal fee: $300–$700 (required by most lenders)
  • Title insurance & search: $500–$1,500
  • Recording fees: $50–$250 (varies by county)
  • Prepaid interest: days from closing to end of month
  • Escrow setup: 2–3 months of taxes and insurance
2026 benchmark: Total closing costs average 2%–3% for a standard rate-and-term refinance. Cash-out refis, jumbo loans, and certain states run higher (up to 5%). Ask your lender for a Loan Estimate (LE) for the exact figure.
New loan term
yr
Or type any term (1–40 years)
Expected years in home
Counted from refi date — not from original loan start
+
The holding period is the single most important input for the exit decision.
Closing costs are a fixed upfront expense — the longer you stay, the more months of savings offset them.
  • Under 3 years: Rarely worth refinancing unless rate drop is large (2%+)
  • 3–7 years: Most common sweet spot — check the break-even tab
  • 7+ years: Refinancing almost always advantageous if rate drops ≥ 0.5%
If unsure, use your best estimate. You can adjust the slider to model different scenarios.
yr
1 yr 40 yr
Results Snapshot
Balance at Refi
$—
After recast / paydown
New Monthly Payment
$—
vs $— current
Monthly Savings
$—
Break-even
—
Months to recover closing costs
Closing Costs
$—
Current Loan
Interest paid to date
$—
Current Loan
Interest remaining
$—
If you don't refinance
New Loan
Total interest
$—
Over full new term
⚠ APR not shown.
The Annual Percentage Rate (APR) — which reflects the true cost of credit including lender origination fees, discount points, mortgage insurance, and other finance charges as defined under the Truth in Lending Act (TILA / Regulation Z, 12 C.F.R. §1026.18) — is not calculated or displayed in this tool. The monthly payment shown is based solely on the interest rate, loan balance, and term you entered. It does not include escrow components (property tax, homeowner's insurance), HOA dues, or private mortgage insurance (PMI). The actual monthly payment on any refinanced loan will differ. To obtain an APR and a binding payment disclosure, request a Loan Estimate (LE) from a licensed lender — lenders are required to provide an LE within 3 business days of receiving your loan application under RESPA / Regulation X.
Sale assumptions — enter to see the proceeds ledger below
Estimated sale price
Agent commission % +
Post-NAR settlement (Aug 2024): Seller typically pays listing agent only.
  • Listing agent (seller pays): 2.5%–3.0%
  • Buyer's agent: now negotiated separately — buyer may pay directly
  • If covering both sides: enter 4.5%–5.5%
Default 3.0% reflects listing-agent-only model. Adjust to match your agreed commission.
Legal / conveyancing ($) +
Other selling costs ($)
Loan type
Current loan — historical payments (years 1 to —)
Year Principal paid Interest paid Balance remaining % to interest
Refinance at end of year — · Balance: —
New refinanced loan — year-by-year (years 1 to —)
Year (new loan) Principal paid Interest paid Balance remaining % to interest
New loan amortization (first 5 years shown)
Month Payment Principal Interest Balance

Current Loan

Monthly payment—
Remaining term—
Total interest (full loan life)—
Interest paid to date—
Interest remaining—
Total cost remaining (principal + interest)—
Rate—

New Refinanced Loan

Monthly payment—
Loan term—
Total interest—
Closing costs —
Total cost (principal + interest + closing)—
Rate—
Current loan (cumulative interest)
New refinanced loan (cumulative interest)
Hover over the chart to compare cumulative interest at any point in time
How to Use This Calculator
Step-by-step guide for the Refinance Analyser and Loan Analyser
Mathematical Methodology & Modelling Assumptions Expand ▾

Core Amortisation Formula

M = P × [ r(1+r)ⁿ ] ÷ [ (1+r)ⁿ − 1 ]

Where M = monthly principal & interest payment, P = loan principal ($), r = monthly interest rate (annual rate ÷ 12 ÷ 100), and n = total number of payments (term in years × 12).

This is the standard US fixed-rate mortgage annuity formula used by CFPB tools, Freddie Mac, and all major lenders. It produces the constant monthly payment that fully amortises the loan over the stated term at a fixed interest rate.

Remaining Balance (Closed-Form)

B = P(1+r)ⁿ − M × [(1+r)ⁿ − 1] ÷ r

This closed-form expression calculates the remaining principal balance after any number of payments n without iterating through each payment individually. It is algebraically equivalent to a month-by-month loop and is used throughout this calculator for instant, zero-latency balance lookups.

Break-Even Calculation

Break-even (months) = Closing Costs ($) ÷ Monthly Savings ($)

Monthly savings = Old monthly P&I − New monthly P&I. Break-even is only calculated when closing costs are paid out-of-pocket. When closing costs are financed into the loan, no upfront cash is required — the calculator instead shows the incremental lifetime interest cost of financing those closing dollars.

True Total Cost Comparison (Exit Decision)

True Total Cost = Payments Made + OOP Closing + Remaining Balance at Sale

This nominal cash-flow comparison includes the remaining loan balance because it is repaid in full from sale proceeds — a real dollar outflow. Including it creates an apples-to-apples comparison between a shorter-term Path A and a longer-term Path B, regardless of their differing amortisation schedules. This is the same methodology used by CFPB consumer tools and leading mortgage rate comparison platforms.

Indicative Net Proceeds Ledger

Net Proceeds = Sale Price − Loan Balance − Agent Fee − Legal − Other − Discharge − Per Diem − Prepayment Penalty

Agent commission is applied to sale price (post-NAR settlement default: 3.0% listing-agent only). Loan discharge fee: flat $300 estimate (range $75–$500+ by state). Per diem interest: balance × (annual rate ÷ 365) × 15 days. Prepayment penalty (conventional only): max 2% of balance in loan years 1–2, max 1% in year 3, $0 thereafter per Dodd-Frank §1026.43(g). FHA, VA, USDA, and physician loans: $0 penalty by law or program design. All figures are pre-tax estimates.

Performance: All calculations execute as pure client-side JavaScript functions with no network requests. DOM updates are synchronous and target fewer than 40 element writes per interaction, keeping Interaction to Next Paint (INP) comfortably below Google's 200ms threshold on all modern devices. No frameworks, no build step, no external data dependencies beyond the Chart.js rendering library.