Mortgage Calculators for San Jose Buyers and Homeowners
Five calculators built for Bay Area numbers: monthly payment with taxes and insurance, how much house you can afford, whether a refinance breaks even, your debt-to-income ratio, and what extra payments do to your payoff date.
- Principal & interest
- Taxes
- Insurance
- HOA
- Mortgage insurance (est.)
- Total interest over the loan
Estimates only. Taxes, insurance, HOA and mortgage insurance vary by property and program. Get real numbers from Rosalio before you make an offer.
- Max total housing payment
- Estimated payment at that price
- Principal & interest
- Your current DTI (debts only)
Assumes about 0.35% per year for insurance and no HOA. A pre-approval replaces all of this with real numbers.
- Current P&I payment
- New P&I payment
- Monthly savings
- Net after 5 years
- Lifetime difference (incl. costs)
Green means you break even inside 3 years. If you plan to sell or move before the break-even month, the refinance probably does not pay for itself.
- Front-end (housing only)
- Room left under 43%
Lenders count the minimum payment on your credit report, not what you actually pay. Rent and utilities do not count as debts.
- New monthly payment
- Years to pay off (normal)
- Years to pay off (with extra)
Make sure extra payments are applied to principal. Most servicers have a checkbox or a separate line for it.
What these calculators can and cannot tell you
They are good at showing direction and scale. They are not a quote.
Payment calculator
Shows the full monthly cost, not just principal and interest. Property tax in Santa Clara County is the line most buyers underestimate. Mortgage insurance is estimated when the down payment is under 20%.
Affordability
Works backward from your income and debts to a target price using a 43% debt-to-income cap. Slide the DTI down to 36% to see a more conservative number that leaves breathing room.
Refinance break-even
Compares your current loan to a new one and tells you the month the savings cover the costs. If that month is after you plan to sell, keep your loan.
Debt-to-income
The ratio underwriters actually use. Lenders count minimum payments on your credit report, not what you choose to pay, and rent does not count as a debt.
Extra payments
Even a few hundred dollars a month toward principal on a Bay Area loan can cut years and six figures of interest. Compare this to a refinance before you pay closing costs.
Get real numbers
A pre-approval replaces every estimate here with actual rates, taxes for the specific property and cash to close.
Talk to Rosalio →Calculator questions
How accurate is the mortgage payment calculator?
The principal and interest math is exact for a fixed-rate loan. Taxes, insurance, HOA and mortgage insurance are estimates based on what you enter. Santa Clara County property tax runs around 1.25% of purchase price per year including local assessments, which is the default used here.
What debt-to-income ratio do I need for a mortgage?
Most programs approve up to about 43% back-end DTI, and some go to 50% with strong credit or reserves. Under 36% is the comfortable zone. The DTI calculator shows where you land and how much room you have.
How do I know if a refinance is worth it?
Divide the closing costs by your monthly savings. That is your break-even month. If you plan to keep the home well past that month, the refinance pays. The refinance calculator does this for you.
Can I get real numbers instead of estimates?
Yes. A pre-approval with Rosalio replaces every estimate on this page with real rates, real taxes for the property and a real cash-to-close figure. It is free and takes about 15 minutes online.
Next step: read about purchase loans, refinancing, or buying your first home. Prefer Spanish? Las calculadoras en español.