Mortgage Calculator
Calculate your monthly PITI mortgage payment — principal, interest, property taxes, homeowner's insurance, and PMI. See a full 30-year amortization schedule and total loan cost.
Your Monthly EMI
₹2,528
Principal
₹4,00,000
Total Interest
₹5,10,178
Total Payable
₹9,10,178
Breakdown
Principal: ₹4,00,000 (44%)
Total Interest: ₹5,10,178 (56%)
Interest-to-Principal: 127.5%
📊 Interactive EMI Breakdown
Principal vs Interest
Year-by-Year Payment Split
Loan Scenario Comparison
| Metric | Your plan | +1% Interest (7.5%) | +12 Months (372mo) |
|---|---|---|---|
| Monthly EMI | ₹2,528 | ₹2,797 ↑ ₹269 | ₹2,502 ↓ ₹26 |
| Total Interest | ₹5,10,178 | ₹6,06,869 ↑ ₹96,691 | ₹5,30,767 ↑ ₹20,589 |
| Total Payable | ₹9,10,178 | ₹10,06,869 | ₹9,30,767 |
📐 How Mortgage is Calculated
Determine loan amount
Home price $400,000 − Down payment $80,000 (20%)= Loan amount: $320,000
Calculate monthly P&I
M = $320,000 × [0.005417 × 1.005417^360] / [1.005417^360 − 1]= Monthly P&I: $2,023
Add escrow (taxes + insurance)
Property tax $400K × 1.2% ÷ 12 = $400 | Insurance = $150/mo= Escrow: $550/month
Total PITI payment
$2,023 + $550= Monthly PITI: $2,573
Rate Comparison
30-Year Fixed
$2,023/mo P&I
Total interest: $408,808 | Lower payment, maximum flexibility
15-Year Fixed
$2,789/mo P&I
Total interest: $182,020 | Saves $226,788 in interest!
The Real Cost of a Mortgage
💡 How Mortgage Payments Are Calculated — The PITI Formula
The Amortization Formula — How Your Mortgage Balance Shrinks
Mortgage amortization uses the formula M = P × [r(1+r)^n] / [(1+r)^n − 1] to calculate a fixed monthly payment that fully retires the loan over the term. Each payment is applied first to the accrued interest for the month, with the remainder reducing principal.
On a $320,000 loan at 6.5% for 30 years:
- Month 1: $1,733 interest + $290 principal (86% interest)
- Month 60 (Year 5): $1,664 interest + $359 principal
- Month 180 (Year 15): $1,468 interest + $555 principal
- Month 300 (Year 25): $886 interest + $1,137 principal
- Month 360 (Final): $11 interest + $2,012 principal
This front-loading is why early prepayments are so powerful — every extra dollar paid in the first 5 years eliminates 3–5× its value in future interest.
PMI: What It Costs and When It Goes Away
Private Mortgage Insurance protects the lender (not you) if you default with less than 20% equity. Key facts:
- Cost: 0.3%–1.5% of original loan amount annually. At 0.8% on a $350,000 loan: $233/month.
- Credit score impact: 760+ score → 0.3% PMI. 680 score → 0.8% PMI. 620 score → 1.2% PMI.
- Automatic cancellation: At 78% LTV (per Homeowners Protection Act of 1998).
- Requested cancellation: At 80% LTV with a good payment history and property appraisal.
- FHA MIP: Different from PMI — required for the life of the loan if down payment < 10%.
Understanding Mortgage Rate Factors
Your mortgage rate is determined by multiple factors layered on top of the base rate set by bond market conditions:
- Credit score: 740+ = lowest rates. Each 20-point drop typically adds 0.1–0.25% to your rate.
- Loan-to-value (LTV): Higher LTV = higher rate. 95% LTV pays 0.25–0.5% more than 80% LTV.
- Loan type: Conventional, FHA, VA, and USDA each have different rate structures.
- Loan size: Conforming loans (≤$766,550) get better rates than jumbo loans.
- Loan term: 15-year rates are typically 0.5–0.75% lower than 30-year rates.
- Points: You can pay points upfront (1 point = 1% of loan) to permanently lower the rate.
30-Year vs. 15-Year Mortgage: A Complete Comparison
| Factor | 30-Year Fixed | 15-Year Fixed |
|---|---|---|
| Interest rate (typical) | 6.50% | 5.75% |
| Monthly P&I ($320K loan) | $2,023 | $2,659 |
| Total interest paid | $408,808 | $158,574 |
| Interest savings | — | $250,234 |
| Equity at year 5 | $17,200 | $59,000 |
| Best for | Cash flow priority | Wealth building |
How Extra Payments Accelerate Mortgage Payoff
On a $320,000 mortgage at 6.5% (30 years, $2,023/month):
- Extra $100/month: Pays off 4.5 years early, saves $52,000 in interest
- Extra $300/month: Pays off 8 years early, saves $117,000 in interest
- Extra $500/month: Pays off 10 years early, saves $158,000 in interest
- Biweekly payments (half payment every 2 weeks): Pays off 4–5 years early, saves $56,000+