Boat Loan Calculator
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years
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Results
Monthly Payment
$427.33
Total Cost
$60,279.16
≈ 5 years of state college
Total Interest$15,279.16
Loan Amount$36,000.00
Out-the-Door Price$45,000.00
Sales Tax$0.00
Loan-to-Value80%
Down Payment20%
Total Payments$51,279.16
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.