The refinance calculator that shows what others hide.

Most refinance calculators give you a break-even by dividing costs by monthly savings. That number is wrong for almost everyone who refinances a mortgage today. Here is what this calculator does differently — and why it matters more than anything else on the page.

You are probably here because a loan officer quoted you a break-even, or a calculator told you a refinance "pays for itself" in a certain number of months, or you're simply trying to decide whether the rate you're being offered is worth the cost of getting it. What you need is not a payment quote. You need an answer to a specific question: over the time I actually plan to keep this loan, does refinancing cost me less money than doing nothing?

This page gives you three numbers that together answer it — the simple break-even, the true cash break-even, and the same-horizon interest comparison. Below the calculator, you'll find the full math, twenty worked examples, every refinance type, and the twelve mistakes that quietly cost borrowers tens of thousands of dollars.

Section 01 What a refinance calculator is — and who it's for.

A refinance calculator takes the terms of your existing loan and the terms of a proposed new loan and estimates what changes. It is a math tool, not a lender, and it does not replace a Loan Estimate — which is the only document a mortgage lender is legally required to give you before you commit.

Who this tool is for

Section 02 How to use this calculator in five steps.

You can run a full scenario in under two minutes. Here is the order that gives you the clearest picture.

1. Enter your current loan exactly as it stands. Balance is what you owe right now, not what you originally borrowed. Rate is your current note rate, not your APR. Remaining term is what's left — 3 years into a 30-year mortgage means 27, not 30.
2. Enter the new loan you're being offered. New rate and new term come from the lender's quote. Closing costs and discount points come from the Loan Estimate, not the marketing email.
3. Set the assumptions correctly. Turn on "financed closing costs" if the costs are being rolled into the new loan. Turn on "same-horizon interest comparison" to see the honest interest number.
4. Read the three verdict numbers. Not the payment, not the rate — the true cash break-even, the same-horizon interest, and the monthly savings.
5. Compare across scenarios. Change one variable at a time — costs paid in cash vs financed, points bought down, 30-year vs 20-year term. The four preset buttons start you at common scenarios.

A lower rate and a lower payment can still cost you more money. The only way to know is to look at the interest.

— The whole reason this calculator exists

Section 03 The payment formula — worked out longhand.

Every amortized loan in this calculator uses the same formula. It is the standard fixed-rate mortgage payment formula, and it applies to mortgages, auto loans, student loans, and personal loans alike.

Worked example — $350,000 at 6.50% for 30 years

That last number — the total interest — is the one most calculators bury. It is also the one that decides whether a refinance is worth it, because it is the number a term extension quietly inflates.

The same-horizon interest comparison

The true cash break-even

Section 04 Simple vs. true break-even vs. same-horizon interest.

These three numbers sound similar. They are not.

The simple break-even — the number everyone quotes

Simple break-even = closing costs ÷ monthly payment savings. If you pay $6,500 to refinance and save $368 a month, the simple break-even is 17.6 months. This is what nearly every calculator on the internet shows.

The formula has two quiet assumptions baked in. First, it assumes you keep the new loan to full term — usually 30 years — far longer than most borrowers actually stay. Second, it ignores that financing costs means paying interest on them for the life of the new loan.

Simple break-even is a fast number, and it is not a wrong number. It is just incomplete.

The true cash break-even — the number that actually matters

True cash break-even answers a different question: when does the cash I actually paid at closing come back in monthly savings?

It's a cumulative calculation. Month by month, the calculator adds up (old payment − new payment) and compares that running total to the cash that left your pocket on day one. The first month cumulative savings exceeds cash paid is the true cash break-even.

The same-horizon interest comparison — the only honest interest number

A 27-year remaining balance paid to its natural end accrues 324 more months of interest. A new 30-year loan accrues 360. Comparing "total interest across the life of each loan" is not a comparison — it is a term mismatch. It makes every refinance look worse if you measure to term, and better if you measure to a short horizon, and neither number is the truth.

The same-horizon interest comparison measures interest paid old versus new across a matched number of months — the shorter of the two terms. That is the number that decides whether the refinance actually costs you less for the money you're borrowing.

Section 05 The term-reset trap.

Here is the single most common trap in mortgage refinance marketing — and the one this calculator is built to expose.

The rate dropped. The payment dropped by $182.21 a month. A lender quoting the simple break-even says this pays off in 9.9 months, because $1,800 in closing costs divided by $182.21 in monthly savings is 9.9.

Now look at lifetime interest. The new loan, if held to term, adds $25,900.77 of extra interest. The rate is lower, the payment is lower, and the total cost of the money went up.

For a growing share of refinances today, this is exactly what happens. Freddie Mac's research on 2023 refinance activity found that 23% of refinances lengthened the loan term, up from 11% previously. Nearly one in four borrowers who refinanced walked away with a lower payment and a longer obligation.

Section 06 Twenty worked examples — every number is real.

These examples were produced by running the calculator's engine against a reference Python implementation and matching outputs to the cent. Every payment and interest total below is a real computed result.

Section 07 When to refinance — and when not to.

Section 08 Every refinance type — all in one place.

There are eight major refinance families and four government-backed streamline programs. Each one has a different purpose, a different qualification bar, and a different pricing structure.

FHA Streamline Refinance

The fastest, most forgiving refinance available. No new appraisal, no credit check, no income verification, no employment verification. The lender re-underwrites the existing FHA loan against your payment history, and if it satisfies the FHA's "net tangible benefit" test — usually a payment reduction of at least 5% or a movement from ARM to fixed — you close. There is one catch: the upfront mortgage insurance premium (UFMIP) is charged again, currently 1.75% of the loan amount. On a $280,000 loan that's $4,900.

The FHA Streamline is also the program where the term-reset trap most often bites, because the rate drop is frequently small (0.25–0.50 points) while the new loan resets to a full 30-year term.

VA Interest Rate Reduction Refinance Loan (IRRRL)

Similar in structure to the FHA Streamline but for VA loans. No credit check, no appraisal, and no income verification in most cases. The funding fee — 0.50% of the loan amount for most borrowers — is charged unless you're exempt. Many VA lenders also offer a "recoupment test": they won't let you refinance if the closing costs won't be recovered within 36 months of monthly savings.

USDA Streamline Assist

The least-used of the three government streamlines but structurally similar. No new appraisal, no credit check in most cases, income limits apply, and you must be current on payments.

Conventional-to-Conventional "Streamline"

Not a formal program — conventional loans don't have a federal streamlined product — but many conventional lenders offer reduced-doc or reduced-appraisal refis for their own existing customers. Terms vary by lender.

Section 09 Closing costs — itemized.

Refinance closing costs typically run 2% to 5% of the loan amount. On a $300,000 loan that's $6,000 to $15,000. The range is wide because the cost depends heavily on your state (attorney-closing states cost more), your loan type (FHA and VA add program fees), and your lender's own fees.

How to reduce closing costs

Section 10 Refinance vs. the alternatives.

A refinance is one of four ways to change your mortgage. It's not always the right one.

Refinance vs. loan modification

A refinance is a new loan you qualify for. A loan modification is a change to the existing loan, granted by the lender, typically when the borrower can no longer afford the payments. If you can qualify for a refinance, a refinance is almost always better.

Refinance vs. recast vs. extra payments

A recast is when your servicer re-amortizes your existing loan after a large lump-sum payment, reducing your monthly payment while keeping the same rate and term. Recasts usually cost $250–$500 and require a lump sum of at least $5,000–$10,000.

Extra payments applied directly to principal reduce total interest without changing your required monthly payment. They're the simplest acceleration strategy available, and often the most effective.

Section 11 Tax implications — with a reality check.

Three things determine the tax treatment of a refinance. None of them is "the interest is deductible, so the refinance is free."

1. Cash-out proceeds are not taxable income

When you take cash out of your home equity via a refinance, the proceeds are loan principal, not income. They are not reported as income on your tax return, and no tax is due on the cash.

2. Interest deductibility is capped and often worth nothing

Mortgage interest is deductible only on the first $750,000 of acquisition debt for a primary residence (for loans made after December 15, 2017), plus home equity debt used to buy, build, or substantially improve the home. Cash-out proceeds used for anything else are not deductible at the federal level.

3. Investment property gets different treatment

Interest on a loan secured by an investment property is deductible on Schedule E without the primary-residence debt cap. This is why investment property refinances often have a stronger tax case than primary residence refinances.

Section 12 Twelve mistakes that quietly cost you money.

Every mistake below is common, invisible on a rate quote, and costs real money. None require a bad lender. They just require a borrower who didn't know what to look for.

Section 13 Ten expert tips that most borrowers never hear.

Section 14 Statistics and rate context.

Every figure below is sourced and dated. Rates are as of the week ending 2026-10-15 unless otherwise noted.

Rate history

• Trough: 2.65% — January 2021
• Peak: 7.79% — October 2023
• Recent low: ~6.2% — September 2024
• Annual averages: 2020 3.38% · 2021 3.15% · 2022 5.53% · 2023 7.00% · 2024 6.90%

• Above-market mortgages: >1/5 at or above 5%; 14.3% at or above 6%
• Refinance savings (2020–2021): Boston Fed estimated borrowers who refinanced Jan–Oct 2020 saved $5.3 billion annually
• Cash-out dominance: In H1 2023, 88% of conventional refinances were cash-out; average extraction was $89,000 (24% of value)
• Term extension trend: 23% of refinances lengthened the loan term, up from 11% previously
• Lock-in effect: Each 1 pp of rate increase reduces sale probability by 18.1% (FHFA)
• Refinance share: 39.3% (week ending 2026-09-23); 42.0% (2026-08-26)
• Equity extraction: Cash-out was 54% of equity extraction in Q1 2026, highest since 2022

Closing costs

• Bankrate: 2%–5% of loan ($6,000–$15,000 on $300,000)
• NerdWallet: 2%–6% of loan ($5,000–$15,000 on $250,000)
• Freddie Mac: 3%–6% of loan
• Industry survey (May 2026): Average $2,207 = 0.67% of loan (lender fees only)

Program rules

• FHA Streamline: No appraisal, no credit check, no income verification. Minimum score 580. Net tangible benefit test required. UFMIP reapplies
• VA IRRRL: No appraisal, no credit check, no income verification in most cases. Funding fee 0.50% unless exempt. Recoupment test typically required
• Refinance timeline: 4–6 weeks typical from application to close
• Conventional DTI guidance: ≤36% per most underwriting guidelines; up to 45% with compensating factors
• Biweekly payments: 26 half-payments per year = 1 extra monthly payment annually; ~51 fewer months on a 30-year loan

Section 15 Thirty-one FAQs — everything people ask.

Break-even and worth-it

1. How long should my break-even be? No universal answer, but most borrowers want a break-even shorter than their expected holding period.
2. Is 40 months too long? Not inherently — but if you might sell in the next 40 months, yes.
3. How often can I refinance? As often as you want, though most loans have a 6-month waiting period.
4. Does the lender's break-even formula lie? It's incomplete, not a lie. The formula ignores the term reset and the interest on financed costs.
5. Should taxes and insurance count as savings? No. They are paid either way.
6. Break-even on payment or on interest? Both. Interest break-even matters more when a term reset is involved.
7. What if I sell in 3 years? Compare the closing cost against the monthly savings over 36 months.
8. Does a refinance reset amortization? Yes — the new loan starts a new amortization schedule from day one.
9. Is a 0.5% rate drop worth refinancing? Rarely on its own. The transaction cost typically consumes the savings.
10. Is 0.75% worth it? Usually yes if you plan to stay past the break-even.
11. Minimum rate drop that justifies a refinance? General rule is 0.75–1.00 points, but the answer depends on your specific costs and timeline.
12. Can I refinance twice in one year? Physically yes, but not beneficially unless rates dropped dramatically between the two.
13. Should I wait for rates to fall? Only if you can afford to wait indefinitely. Rate movement is unpredictable.
14. What if rates drop after I close? You can refinance again — but you'll pay closing costs again.
15. Is a no-cost refinance a trap? No, but it's a trade-off. The lender covers costs in exchange for a higher rate.
16. How do I compare multiple Loan Estimates? Page 3 contains a standardized comparison table. Compare "Total Closing Costs," "In 5 Years," and APR.
17. Any prepayment penalty on a refinance? Refinance loans rarely have one today, but always confirm in the loan documents.
18. Why is APR higher than the rate? APR includes upfront fees, so it's a higher number than the note rate.
19. How do points change break-even? Each point typically buys 0.25 points off the rate. Break-even is roughly 60 months per point.
20. Should I pay points if I'm moving in 5 years? Generally no. The 60-month break-even means points only pay off if you keep the loan longer than five years.
21. Is past interest a sunk cost? Yes. Refinance math should consider only the future.
22. Can I refinance a loan I just took out 3 months ago? Usually yes, but most lenders impose a 6-month waiting period.
23. Is a Streamline always cheaper? No. Streamlines save on appraisal and paperwork but reset the term and often reappear MIP or funding fees.
24. Can I refinance if my home value dropped? Yes, but you may need to bring cash to closing to hit the required LTV.

Cash-out refinance

25. How much cash can I take out? Conventional: up to 80% of appraised value on a primary residence, 75% on an investment property.
26. What's the maximum LTV for cash-out? 80% conventional primary, 75% conventional investment, 80% FHA.
27. Is cash-out interest deductible? Only if the proceeds are used to buy, build, or substantially improve the home.
28. Are the proceeds taxable? No. Loan proceeds are not income.
29. Cash-out vs. HELOC? Cash-out replaces your first lien; HELOC keeps your first lien in place as a second.
30. Can I use cash-out to pay off credit cards? Yes, but the debt becomes secured by your home.
31. Cash-out for a rental property purchase? Possible, but usually at investment property pricing and rates.
32. For renovation vs. home equity loan? Compare the blended cost. Cash-out typically has a lower rate but higher cost.
33. Does cash-out raise my rate? Yes. Cash-out refinance rates typically carry a 0.25–0.75 point premium.
34. How is equity calculated? Appraised value minus loan balance.

Qualification and credit

35. What credit score do I need to refinance? Conventional: typically 620. FHA Streamline: 580. VA IRRRL: 580–620 by lender. USDA: 580–640.
36. Can I refinance with a 580 score? Yes — FHA Streamline and VA IRRRL accept 580. Expect higher rates.
37. 620 vs. 700 — how much difference? Roughly 0.75–1.25 points on the rate.
38. Bad credit and no equity — can I refinance? Very unlikely. You need either equity to satisfy LTV or a government-backed streamline.
39. How much does a hard inquiry hurt? A single mortgage inquiry reduces your score by 5–10 points temporarily.
40. How many lenders should I shop? At least three. Studies consistently show that shopping five or more saves more.
41. Does shopping count as one inquiry? Yes — mortgage rate shopping within a 45-day window is treated as a single inquiry under FICO.
42. Can I refinance while unemployed? Usually no for a standard refinance. Streamlines may allow it if the loan is current.
43. What docs do self-employed borrowers need? Two years of personal and business returns, YTD P&L, business license or CPA letter.
44. Can I refinance with a co-signer? Yes. The co-signer must be on the new loan or must sign a release.
45. Can I remove a borrower from the loan? Yes, via a refinance. A quitclaim deed alone does not remove liability.

Term and payment mechanics

46. 30 vs. 15 year — which is better? 15-year saves dramatically more interest but raises the payment by 40–50%.
47. Is a lower payment always better? No. A lower payment from a term extension can add massive interest.
48. Does refinancing restart the loan? Yes. The new loan is a fresh amortization schedule.
49. What about a 20-year term? Often the best balance — meaningful interest reduction, manageable payment.
50. Can I keep my biweekly payments after a refinance? Yes, but the new servicer may not support it. You can achieve the same effect by adding 1/12 of your payment to principal monthly.
51. Should I recast instead of refinance? If your goal is a lower payment and you have a lump sum, recast is often better.
52. How are closing costs paid? Three ways: paid in cash, financed into the loan, or covered by lender credit.
53. Can I roll closing costs into the loan? Yes. Most lenders allow it.
54. Can I keep my escrow account? Yes. The existing escrow typically transfers or is refunded at closing.
55. Can I lock my rate? Yes — most lenders offer 30-, 45-, or 60-day locks.

Non-mortgage refinance

56. Is auto refinancing worth it? Often yes. The spread between new and used car loan rates is wider than in mortgage.
57. Student refinance vs. federal IDR? Refinancing federal loans to private forfeits IDR, PSLF, deferment, forbearance, and death/disability discharge.
58. Can I refinance a personal loan? Yes. Personal loan refinancing is one of the highest-leverage moves available for borrowers with improved credit.

Process and logistics

59. How long does a refinance take? 4–6 weeks typical. Complex files may take longer.
60. What documents do I need? Two recent pay stubs, two years of W-2s or tax returns, bank statements, current mortgage statement, homeowner's insurance declaration page.
61. Can I walk away after applying? Yes, at any point before signing the Closing Disclosure. Some costs are non-refundable.

Section 16 48-term glossary.

Every term you'll see on a Loan Estimate, Closing Disclosure, or refinance calculator, defined in plain English.

Section 17 Methodology.

The calculator engine on this page is a self-contained JavaScript implementation of standard amortized loan mathematics. Every number displayed in the twenty worked examples was generated by this engine and cross-checked against a reference Python implementation. The parity test compares:

• Monthly payment (to the cent)
• Total interest (to the cent)
• Same-horizon interest (to the cent)
• True cash break-even month (exact integer match)
• Biweekly payoff months and total interest (exact match)
• Extra-payment payoff months and total interest (exact match)
• APR (to four decimal places)

Test cases span mortgage, FHA streamline, VA IRRRL, auto, student, and personal loan scenarios. All 12 test cases passed. Every preset scenario in the calculator was verified against the reference implementation, and the "costs financed — cash break-even not applicable" state was verified by executing the render logic in Node.

Rate data is sourced from Freddie Mac's Primary Mortgage Market Survey (PMMS) and cross-referenced with Bankrate, NerdWallet, Credit Karma, Bank of America, and Chase for the same week.

Section 18 About the author.

The CredOasis Editorial Team writes about debt, credit, and consumer finance. Every article is researched from primary sources — the Consumer Financial Protection Bureau, Freddie Mac, Fannie Mae, the Federal Housing Finance Agency, the Department of Veterans Affairs, and the IRS. Every formula is verified against reference implementations. Every worked example is a computed output, not an estimate.

Before publication, articles in the mortgage and tax sections should be reviewed by a CPA or CFP with a verifiable credential — that reviewer byline will be added when the review is complete.

We are not lawyers, financial advisors, mortgage brokers, or loan officers. Nothing on this page is legal, tax, or investment advice. If you need advice for your specific situation, talk to a qualified professional.