How this number is made
An amortizing loan keeps the payment flat while the interest slice shrinks and the principal slice grows. This page is the summary of that schedule.
- Enter the amount financed, not the purchase price, if you already put money down.
- Years are the term the payment is built on.
Formula
Payment = P × r(1+r)^n ÷ ((1+r)^n − 1). Total interest = payment × months − P. First-year interest is the sum of balance × r for the first twelve months.
Worked example
With the figures already in the form, monthly principal and interest is $1,769.79.
Questions
Where is the full month-by-month table?
The headline is the payment and the rows are the totals. A 360-row table is the same formula repeated. The mortgage page charts the year-by-year shift.
Why is year one mostly interest?
Interest is charged on the whole balance. Early payments barely move that balance, so the interest slice stays large.