Mortgage Calculator
Full PITI payment breakdown with PMI, HOA, property tax & insurance — plus affordability check, extra payment payoff, refinance comparison, and ARM vs. fixed analysis. All live as you type.
30-yr avg Mar 2026: ~6.65%
US avg ≈1.1% of home value/yr
US avg ≈$1,500–$2,500/yr
US avg ≈$291/mo (if applicable)
Typical 0.3–1.9% if <20% down
What Is a Mortgage?
A mortgage is a loan specifically designed for purchasing real estate. When you buy a home but don't have the full purchase price in cash — which is nearly everyone — you borrow the difference from a lender (bank, credit union, or mortgage company). The property itself serves as collateral: if you stop making payments, the lender has the legal right to take ownership of the home through a process called foreclosure.
You repay a mortgage through fixed monthly payments over a set term — most commonly 15 or 30 years. Each payment consists of four components known as PITI: Principal (reducing your loan balance), Interest (the lender's fee for lending you money), Taxes (your property tax collected monthly and paid on your behalf), and Insurance (homeowners insurance). If your down payment is below 20%, a fifth cost is added: PMI (private mortgage insurance).
The core mortgage equation: On a $400,000 home with a 20% down payment ($80,000), you'd borrow $320,000 at today's average 30-year rate of ~6.65%. Your monthly principal and interest payment would be approximately $2,057. Add property tax (~$417/mo), homeowners insurance (~$150/mo), and you're looking at a total monthly housing cost of roughly $2,624 — before HOA fees, if applicable.
Types of Mortgages
The most common mortgage type is the 30-year fixed-rate — a single rate locked in for the entire loan term, giving you predictable payments for three decades. A 15-year fixed has higher monthly payments but dramatically less interest paid overall and builds equity twice as fast. Adjustable-rate mortgages (ARMs) — like the 5/1 ARM — offer a lower initial rate for a fixed period, then adjust annually based on market rates. Government-backed loans include FHA (low down payment, flexible credit requirements), VA (zero down for eligible veterans, no PMI), and USDA (zero down for rural areas, income limits apply).
What Is a Mortgage Calculator and What Does It Do?
A mortgage calculator computes your estimated monthly payment and the full cost of your loan over its lifetime. A basic mortgage calculator only gives you the principal and interest payment — but that's only part of the picture. A comprehensive calculator adds property taxes, homeowners insurance, PMI, and HOA fees to show your true PITI payment. The CatchyTools mortgage calculator goes further still, with five specialized modes that answer the most important questions homebuyers, homeowners, and refinancers actually face.
Full PITI breakdown with a live donut chart, PMI auto-detection, loan type selector (Conventional, FHA, VA, USDA), payment frequency options (monthly, bi-weekly, weekly), and a complete amortization schedule. Shows your exact payoff date and total lifetime cost.
Reverse-calculates the maximum home price you can afford based on your income, debts, down payment, and the 28/36 DTI rule. Live gauges show exactly how close you are to both the front-end (housing) and back-end (all debts) debt-to-income limits.
Shows exactly how much interest you save and how many years you cut off your loan by making extra monthly payments, lump-sum payments, or bi-weekly payments. Side-by-side comparison of standard vs. accelerated payoff.
Compares your current mortgage against a refinanced mortgage — showing monthly savings, break-even point in months, and lifetime interest impact. Includes closing cost modeling to show the true payback period.
Models any ARM type (3/1, 5/1, 7/1, 10/1) against a fixed-rate loan. Shows initial ARM savings, post-adjustment payment shock, lifetime interest difference, and which loan type wins for your specific holding period.
How Mortgage Payments Are Calculated
The principal and interest (P&I) portion of your mortgage payment is calculated using the standard amortization formula: M = P × [r(1+r)^n] / [(1+r)^n – 1] — where M is your monthly payment, P is the loan principal, r is your monthly interest rate (annual rate ÷ 12), and n is the total number of payments (years × 12). The result is a fixed monthly payment that remains constant for the life of a fixed-rate loan.
Why Early Payments Are Mostly Interest
Amortization causes the split between principal and interest to shift dramatically over time. In year one of a 30-year mortgage at 6.75%, roughly 84% of each payment goes to interest and only 16% to principal. By year 20, the split reverses to about 55% principal and 45% interest. This is why extra early payments are so powerful — every extra dollar of principal paid in the first years eliminates years of interest that compounds on a large balance.
Bi-weekly payment trick: Instead of making 12 monthly payments per year, pay half your monthly payment every two weeks. Because there are 52 weeks in a year (26 bi-weekly periods), you make the equivalent of 13 full monthly payments per year — one extra payment annually. On a $320,000 loan at 6.75% over 30 years, this cuts approximately 4–5 years off your loan and saves over $50,000 in interest with zero change to your lifestyle.
What Competitors Miss — PITI vs. PI
Most competitors show only the principal and interest payment. But your actual out-of-pocket housing cost includes property taxes, homeowners insurance, HOA fees, and PMI. On the median US home ($410,800), the difference between the PI-only payment and the full PITI payment is often $600–$1,200 per month — a gap large enough to completely change your affordability picture. Always use a calculator that shows full PITI to avoid surprises after closing.
Current Mortgage Rates — March 2026
After the Federal Reserve's three rate cuts in late 2025, mortgage rates dipped briefly in late February 2026 to their lowest levels in three years before rebounding. As of March 2026, rates remain elevated by historical standards but significantly below the October 2023 peak of 8.0%. Buyers who can tolerate today's rates may benefit from refinancing later if rates continue to fall as many analysts project through 2026–2027.
| Loan Type | Term | Rate (Mar 2026) | APR | Key Notes |
|---|---|---|---|---|
| 30-Year Fixed | 30 yr | ~6.65% | ~6.72% | Most popular; lowest monthly payment |
| 20-Year Fixed | 20 yr | ~6.30% | ~6.38% | Mid-point; good balance |
| 15-Year Fixed | 15 yr | ~5.90% | ~5.99% | Fastest equity build; lower total cost |
| 5/1 ARM | 30 yr | ~6.10% | ~7.20% | Lower initial; rate risk after 5 yr |
| 7/1 ARM | 30 yr | ~6.20% | ~7.00% | Longer fixed period |
| FHA 30-Year | 30 yr | ~6.40% | ~7.20% | Low down payment; MIP required |
| VA 30-Year | 30 yr | ~6.00% | ~6.10% | Best rate; zero down, no PMI |
| USDA 30-Year | 30 yr | ~5.90% | ~6.05% | Rural only; zero down; income limits |
Note: Mortgage rates change daily and vary significantly by lender, credit score, down payment, loan amount, and state. These are market averages for a borrower with a 740+ credit score and 20% down payment. Use the calculator above with your specific rate quote — even 0.25% difference changes lifetime interest by thousands of dollars.
The 28/36 Rule — How Much House Can You Afford?
Lenders use the debt-to-income (DTI) ratio as the primary qualification benchmark. The classic "28/36 rule" says your housing costs (PITI) should not exceed 28% of your gross monthly income, and all monthly debt payments combined (housing + car loans + student loans + credit cards) should not exceed 36%. These thresholds represent the most conservative, financially healthy range.
| Income Level | Max Housing (28%) | Max All Debts (36%) | Max Loan (~30yr, 6.75%) | Max Home Price (20% down) |
|---|---|---|---|---|
| $60,000/yr | $1,400/mo | $1,800/mo | ~$215,000 | ~$270,000 |
| $80,000/yr | $1,867/mo | $2,400/mo | ~$287,000 | ~$359,000 |
| $100,000/yr | $2,333/mo | $3,000/mo | ~$358,000 | ~$448,000 |
| $120,000/yr | $2,800/mo | $3,600/mo | ~$430,000 | ~$537,000 |
| $150,000/yr | $3,500/mo | $4,500/mo | ~$538,000 | ~$672,000 |
In practice, many lenders approve up to a 43–50% back-end DTI, especially with strong credit scores and compensating factors. However, qualifying for a loan and comfortably affording it are different things. The 28/36 rule represents the zone where most financial planners believe homeowners can maintain housing costs while also saving for retirement, building an emergency fund, and avoiding financial stress.
Before talking to lenders: Use the Affordability mode in the calculator above to find your number first. Know your maximum comfortable payment, not just your maximum qualifying payment. The difference between the two is often $300–$600/month — money that could fund retirement, travel, or your emergency fund instead.
PMI — Private Mortgage Insurance Explained
If your down payment is less than 20% on a conventional loan, your lender requires private mortgage insurance (PMI). PMI protects the lender — not you — if you default on the loan. It costs between 0.3% and 1.9% of your loan amount annually, depending on your credit score, loan size, and down payment percentage. On a $320,000 loan at 0.85% PMI, that's $2,720 per year ($227 per month) added to your payment.
When Does PMI End?
Under the Homeowners Protection Act, lenders must automatically cancel PMI when your loan-to-value ratio (LTV) reaches 78% — meaning you've paid down 22% of the original home value. You can also request cancellation at 80% LTV (20% equity). On a $400,000 home with 10% down, PMI would automatically drop off around year 7–8 at a 6.75% rate. The calculator shows this exact PMI drop-off date in the PITI breakdown.
FHA vs. Conventional PMI: FHA loans require mortgage insurance premium (MIP) for the life of the loan if your down payment is less than 10% — it never drops off. On a conventional loan, PMI eventually disappears. This is a major reason why borrowers with 10–20% down often choose conventional loans over FHA, even if the FHA interest rate is slightly lower. Run both scenarios in the calculator to compare total lifetime costs.
Should You Refinance Your Mortgage?
Refinancing replaces your existing mortgage with a new one — usually to get a lower interest rate, lower monthly payment, shorten the loan term, or tap equity. The key financial question is: do the long-term monthly savings outweigh the upfront closing costs (typically $2,000–$6,000)? The break-even point tells you how many months it takes to recoup those costs through lower payments.
The Break-Even Analysis
If refinancing costs $4,000 in closing costs and saves you $200 per month, your break-even point is 20 months. If you plan to stay in the home for more than 20 months — likely — refinancing makes financial sense. If you might move in the next year or two, you'd pay the closing costs but not live long enough to capture the savings. The Refinance mode in the calculator does this exact math instantly.
The 1% rule: A commonly cited guideline says refinancing makes sense if you can lower your rate by at least 1 percentage point. In March 2026 with rates at ~6.65%, anyone who bought in 2022–2023 at 7.0–8.0% may find refinancing beneficial. Even a 0.5% reduction can save tens of thousands over a 30-year loan depending on your balance.
Related Calculators
The mortgage calculator works best as part of a complete home-buying financial toolkit. These three calculators address the other major costs and decisions that come alongside your mortgage:
Estimate all upfront costs to close on a home — origination fees, title insurance, appraisal, prepaid interest, escrow setup, and more. Buyer and seller breakdown by state and loan type.
For homeowners 62+, explore how much you can borrow against your home equity through a HECM or jumbo reverse mortgage — as a lump sum, monthly payment, or line of credit.
High credit card debt raises your DTI ratio and can block mortgage approval or increase your rate. See how fast you can pay it down before applying for a home loan.
Frequently Asked Questions
A mortgage is a loan used to buy real estate where the property serves as collateral. You borrow the purchase price minus your down payment from a lender, then repay it over a fixed term (typically 15 or 30 years) through monthly payments. Each payment covers principal (loan repayment), interest (the lender's fee), and often taxes and insurance held in escrow. If you stop paying, the lender can foreclose and take ownership of the property. At the end of the term, your loan is fully paid off and you own the home outright.
A mortgage calculator estimates your monthly payment and total loan cost based on the loan amount, interest rate, and term. This calculator uses the industry-standard amortization formula for the principal and interest payment, then adds your property tax, insurance, HOA, and PMI inputs for a full PITI estimate. Accuracy depends on your inputs: the PI calculation is mathematically exact; the tax, insurance, and HOA figures depend on your actual location and coverage. The closer your inputs match your actual situation, the more accurate the result. Always get a formal Loan Estimate from your lender before making commitments.
Minimum credit score requirements vary by loan type: Conventional loans typically require 620+, though the best rates go to 740+ borrowers. FHA loans allow scores as low as 580 (with 3.5% down) or even 500 (with 10% down). VA loans don't have a minimum, but most VA lenders want 580–620+. USDA loans typically require 640+. Your credit score affects not just approval odds but the interest rate you're offered — the difference between a 640 and a 760 score can be 0.5–1.0% in rate, translating to tens of thousands in interest over a 30-year loan. Paying down credit card debt (which lowers your utilization ratio) is one of the fastest ways to boost your score before applying.
The minimum down payment depends on loan type: Conventional loans require as little as 3% (for first-time buyers) or 5% otherwise; FHA requires 3.5%; VA and USDA require 0%. However, putting down less than 20% on a conventional loan requires PMI, which adds 0.3–1.9% of the loan amount per year to your costs. A 20% down payment eliminates PMI entirely, reduces your loan size, lowers your payment, and may qualify you for a better rate. The trade-off: a larger down payment depletes your savings. Most financial advisors suggest keeping 3–6 months of expenses in reserve after the down payment — so a 20% down payment is only ideal if you can achieve it without depleting your emergency fund.
Both have clear advantages. A 15-year mortgage has a lower interest rate (typically 0.5–0.75% less than a 30-year), builds equity twice as fast, and costs dramatically less in total interest — often 60–70% less over the life of the loan. The trade-off is a significantly higher monthly payment (roughly 40–50% more per month for the same loan amount). A 30-year mortgage has lower monthly payments, preserving cash flow for other investments, emergencies, or lifestyle expenses. For most buyers, the question is whether the monthly payment difference could earn more by being invested elsewhere than it would save in mortgage interest. Use the Standard Calculator mode and compare both terms side-by-side to see the exact numbers for your scenario.
PMI (Private Mortgage Insurance) is required on conventional loans when your down payment is less than 20%. It protects the lender if you default — not you. It typically costs 0.3–1.9% of the loan amount per year. You can request cancellation when your LTV reaches 80% (you have 20% equity). Under the Homeowners Protection Act, lenders must automatically cancel PMI when LTV reaches 78%. You can also eliminate PMI by refinancing once you have 20% equity, or by making a large enough principal payment to get below the 80% threshold. The calculator shows you the estimated month your PMI will drop off based on your loan details.
Extra mortgage payments go directly toward reducing your principal balance, which reduces the interest you're charged in every subsequent month. Because mortgage interest is calculated on the remaining balance, a smaller balance means less interest — compounding the savings over time. Even $100–$200 extra per month can cut 3–6 years off a 30-year mortgage and save $30,000–$60,000 in interest. Tell your lender or servicer to apply extra payments to principal only (not toward future payments), or check your loan servicer's online portal to confirm correct application. Use the Extra Payments mode to model your exact savings.
Refinancing makes financial sense when: (1) you can lower your rate by enough to recoup closing costs within your expected remaining time in the home (use the break-even calculation); (2) you want to switch from an ARM to a fixed rate for stability; (3) you want to shorten your term from 30 to 15 years to save on interest; or (4) you need to access equity through a cash-out refinance. The general guideline is a 1% rate reduction to justify refinancing, but even 0.5% can work if you have a large balance and plan to stay long. March 2026 may offer a good window — rates have fallen from their 2023 peak, and many analysts expect further declines, though waiting is always a risk.
The interest rate is the annual cost of borrowing the principal, expressed as a percentage. The APR (Annual Percentage Rate) is a broader measure that includes the interest rate plus other loan costs — such as origination fees, discount points, mortgage broker fees, and certain closing costs — expressed as a yearly rate. The APR gives you a more complete picture of the loan's true annual cost. When comparing mortgage offers from different lenders, comparing APRs is more meaningful than comparing interest rates alone, because two loans with the same stated interest rate but different fees will have different APRs. Always ask lenders for both the rate and APR when comparing offers.
An adjustable-rate mortgage (ARM) has a fixed rate for an initial period (3, 5, 7, or 10 years), then adjusts annually based on a benchmark index (usually the 1-year SOFR or Treasury rate) plus a margin. A 5/1 ARM means fixed for 5 years, then adjusts annually. In March 2026, a 5/1 ARM at ~6.10% is lower than the 30-year fixed at ~6.65%, saving roughly $130/month on a $320,000 loan. The risk: if rates rise significantly after year 5, your payment could increase substantially. ARMs have caps — typically 2% per adjustment and 5–6% lifetime — which limit the worst-case scenario. ARMs can make sense if you plan to sell or refinance before the fixed period ends, or if you expect rates to fall further. Use the ARM vs. Fixed mode to model your specific scenario with current rate assumptions.
This calculator is for educational and planning purposes only and does not constitute financial or mortgage advice. Payment estimates assume a fully amortizing fixed-rate loan. Actual payments, rates, and qualification depend on your credit profile, lender, property, and local tax rates. PMI rates and removal timing vary by lender and loan type. ARM projections assume the adjusted rate is constant after the fixed period — actual ARM rates reset annually. Tax and insurance estimates are national averages and may differ significantly by location. No personal data is collected or stored. ✦ CatchyTools.com