Data-backed assumptions
Rates and affordability assumptions pull from Freddie Mac PMMS averages and U.S. Census Bureau property tax data so payment estimates stay realistic.
Benchmarks refreshed every Thursday after Freddie Mac and Census releases.
AI Smart Mortgage Calculator
Calculate monthly payments, view amortization schedules, and get AI personalized advice. Includes taxes, insurance, PMI, and optimization strategies.
Monthly payment
Amortization schedule
AI guidance
Scenario optimization
Compliance & privacy checklist
All mortgage inputs live in your browser. Every publish passes privacy, disclaimer, and underwriter-readiness reviews.
4-step mortgage planning workflow
Check affordability, secure pre-approval, stress-test contingencies, and sync automation for next steps.
1. Lock in the total housing budget
Combine price, taxes, insurance, HOA dues, and buffers so you know the true monthly obligation before shopping.
2. Align with pre-approval requirements
Compare 15/20/30-year options, adjust credit and LTV assumptions, and document the DTI ratios lenders expect.
3. Stress-test PMI, taxes, and extra payments
Toggle PMI removal dates, tax increases, and lump-sum payments to see how interest and payoff timelines shift.
4. Handoff to ROI & AI tools
Sync amortization data with the ROI and AI calculators so savings, investing, and refinance reminders stay coordinated.
Mortgage Calculator
Calculate your mortgage payment including taxes and insurance
Loan details
20.0% of home price
Additional monthly costs
Applies when the down payment is below 20%
How buyers use this mortgage planner
Case studies tying the mortgage, ROI, and AI workflows together.
First-time buyers targeting a 30-year fixed
Young family wants predictable payments and fast PMI removal.
- •Timeline: Closing in six months with 15% of the price already saved.
- •Plan: Model 6.5%-7.5% rates, push the worst case into the ROI calculator, and confirm emergency reserves before signing.
- •Result: Increase biweekly savings to reach 18% down and schedule PMI cancellation once LTV hits 80%.
2019 borrowers testing refinance math
Need a breakeven view and a plan for freed-up cash flow.
- •Timeline: 24 years remaining on a $420k balance at 5.4%.
- •Plan: Compare a 20-year refinance versus extra payments, then route savings to the AI calculator for reinvestment ideas.
- •Result: Lock a 20-year 4.6% rate and automate investing of the $320/month savings.
Every dataset we cite so you can replicate the math.
Mortgage data stack
Freddie Mac Primary Mortgage Market Survey (PMMS)
Weekly 30Y/15Y fixed averages anchor the rate scenarios and AI fallbacks.
View sourceFHFA House Price Index (HPI)
Used for appreciation stress tests and equity timelines.
View sourceBureau of Labor Statistics CPI
Inflation inputs for escrow estimates and real-dollar comparisons.
View sourceCadence: PMMS each Thursday, FHFA monthly, CPI monthly.
Understanding mortgage calculations
Monthly payment formula
Payments follow the standard amortization formula: M = P[r(1+r)^n] / [(1+r)^n - 1]
- • M = monthly payment
- • P = loan principal
- • r = monthly interest rate
- • n = total number of payments
PMI requirements
Private mortgage insurance applies when the down payment is below 20% of the purchase price.
- • Typical cost: 0.3% to 1.5% annually
- • Can be removed once equity reaches 20%
- • Automatically removed at 22% equity
- • Avoid PMI with a 20%+ down payment
Affordability rules of thumb
Industry-standard ratios lenders use to gauge mortgage affordability.
- • 28% rule: housing costs ≤ 28% of gross income
- • 36% rule: total debt ≤ 36% of income
- • Strong credit may allow debt-to-income up to 43%
- • Include all monthly debt obligations
Mortgage calculator FAQs
How is the monthly payment calculated?
We use the standard amortization formula M = P[r(1+r)^n]/[(1+r)^n-1], where P is the loan amount, r is the monthly interest rate (APR ÷ 12), and n is total payments (loan term × 12).
What is included in the total housing payment?
Monthly housing cost includes principal & interest (P&I), property taxes, homeowners insurance, private mortgage insurance (if required), and HOA dues when applicable—often summarized as “PITI.”
When can I cancel PMI?
Once you reach 20% home equity through payments or appreciation you can usually request removal. By law lenders must drop PMI automatically at 22% equity.
Should I make extra payments?
Extra principal payments shorten the term and reduce interest. Prioritize 401(k) matches, high-interest debt payoff, and an emergency fund first. It makes sense when your mortgage rate is higher than your expected investment return.
Should I pick a 15-year or 30-year mortgage?
A 15-year loan builds equity faster and cuts interest but raises monthly payments. A 30-year keeps payments lower but costs more interest overall. Align the term with your cash flow, other goals, and rate environment.
Examples are educational and not formal underwriting decisions.
Important mortgage disclaimer
Payment projections rely on your inputs plus the datasets above. Always validate with a licensed lender before locking a loan.
Rates, taxes, and insurance premiums change frequently. Cash-flow margins should include buffers for unexpected increases.
FutureValueCalc does not provide individualized legal or financial advice. Consult local professionals for binding quotes.
Turn mortgage insights into automation
Export the amortization schedule to the ROI and AI calculators so savings, investing, and refinance reminders stay in sync.