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Mortgage

Mortgage Calculator

See your real monthly payment with taxes and insurance, and visualize the full amortization. Drag any slider to recalculate instantly.

Updated April 2026 · Rates referenced from Freddie Mac PMMS · Read our methodology

30-Year Fixed

6.81%

15-Year Fixed

6.12%

5/1 ARM

5.92%

7/1 ARM

6.08%

Rates as of Apr 26, 2026 · Source: Freddie Mac PMMS, industry averages

How a mortgage payment is calculated

Your monthly mortgage payment has up to four parts, often abbreviated PITI: Principal, Interest, Taxes, and Insurance. The calculator above adds optional HOA dues for condos or planned communities.

The principal & interest formula

We use the standard fixed-rate mortgage formula:

M = P × ( r(1+r)^n ) / ( (1+r)^n − 1 )

P = loan principal (home price − down payment)
r = monthly interest rate (annual rate ÷ 12)
n = number of monthly payments (term in years × 12)

Methodology & assumptions

  • Fixed interest rate over the full loan term — does not model ARMs or rate resets.
  • Property tax and insurance are entered as annual amounts and divided by 12.
  • Does not include private mortgage insurance (PMI) — typically required when down payment is below 20%.
  • Does not include closing costs, origination fees, or points.
  • Amortization is calculated month-by-month and aggregated to yearly buckets for the chart.

Frequently asked questions

What's a good down payment?
Conventional loans typically require at least 3-5%. Putting 20% down lets you skip PMI and lowers your monthly payment. The slider above adjusts the percentage live.
Should I pick a 15-year or 30-year term?
A 15-year term has higher monthly payments but you pay much less total interest. A 30-year stretches the cost lower per month but you pay more over time. Toggle the term slider above to see the difference.
Why isn't PMI included?
PMI varies widely by lender and credit profile (typically 0.3-1.5% of loan amount per year). We're keeping the math transparent — add 0.5% × loan amount ÷ 12 to your payment if you're under 20% down.
Can I share my scenario?
Yes. Hit "Save & share" — every slider position is encoded in the URL, so the link you copy reproduces your exact numbers for whoever you send it to.

This tool is for educational purposes only and does not constitute financial advice. Consult a licensed mortgage advisor for decisions specific to your situation.

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