Mortgage Calculator
Loan amount, monthly payment and total interest from price, down payment, rate and term.
How it works
Loan = price × (1 − down%); payment via amortized formula
Same as a loan payment after subtracting the down payment. A larger down payment lowers the loan and interest.
FAQ
Is a larger down payment better?
A larger down payment cuts the loan and total interest but ties up cash — balance liquidity against interest cost.
Worked example
Home price 1,000,000, 30% down, 4.2% annual, 30 years:
- Loan = 1,000,000 × 70% = 700,000
- Monthly rate r = 0.042 ÷ 12 = 0.0035, n = 360
- Payment = 700000 × 0.0035 ÷ (1 − 1.0035⁻³⁶⁰) ≈ 3,423
- Total paid ≈ 1,232,000, of which interest ≈ 532,000
Month one is 2,450 interest and only ~973 principal — the "all interest early" effect.
Notes and limitations
The result excludes taxes, insurance, HOA and closing costs, which materially affect affordability. Each 0.1% of rate is roughly 14,000 of total interest on 700,000 over 30 years. If cash flow allows, shortening the term saves more than lowering the payment.