Mortgage Calculator
Inputs
$
Typical: $150K–$750K
$
Typical: 10–20% of home price
%
Enter the rate from your lender or loan estimate — mortgage rates change frequently.
years
Summary
Monthly P&I Payment
$1,769.79
Total Monthly Payment$2,219.79
Loan Amount$280,000.00
Total of All Payments$637,124.57
Total Interest Paid$357,124.57
Amortising loan payment
- 1.Convert the annual rate to a monthly rate
Payments are monthly, so every term in the formula has to be expressed per month.
- 2.Count the payments
The number of monthly payments over the whole term.
- 3.Solve for the level payment
This comes from setting the present value of all n equal payments equal to the amount borrowed, then solving for the payment. The (1+i)ⁿ − 1 in the denominator is the sum of a geometric series — the same series that drains a pension or decays a drug in plasma, which is why one formula family serves calculators across several hubs.
Simon Stevin published the first printed interest tables, including the present value of an annuity — the relationship this payment formula inverts. Until then such tables were guarded as trade secrets by lenders.
Amortization Schedule
360 rows| Month | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| 1 | $1,769.79 | $253.12 | $1,516.67 | $279,746.88 |
| 2 | $1,769.79 | $254.49 | $1,515.30 | $279,492.38 |
| 3 | $1,769.79 | $255.87 | $1,513.92 | $279,236.51 |
| 4 | $1,769.79 | $257.26 | $1,512.53 | $278,979.25 |
| 5 | $1,769.79 | $258.65 | $1,511.14 | $278,720.60 |
| 6 | $1,769.79 | $260.05 | $1,509.74 | $278,460.54 |
| 7 | $1,769.79 | $261.46 | $1,508.33 | $278,199.08 |
| 8 | $1,769.79 | $262.88 | $1,506.91 | $277,936.20 |
| 9 | $1,769.79 | $264.30 | $1,505.49 | $277,671.90 |
| 10 | $1,769.79 | $265.73 | $1,504.06 | $277,406.16 |
| 11 | $1,769.79 | $267.17 | $1,502.62 | $277,138.99 |
| 12 | $1,769.79 | $268.62 | $1,501.17 | $276,870.37 |