Tools / Loan Amortization

Loan Amortization Calculator

Visualize your loan payment breakdown over time. See how much of each payment goes toward interest versus principal.

Loan Details
Optional: Add extra principal each month
Monthly Payment -- --
Total Principal --
Total Interest --
Total Cost --
Payoff Time --
Payment Breakdown Over Time Year 1-30
-- -- --
Year --
Principal --
Interest --
Balance --
Year 1 Year 30
Principal paid
Interest paid
Remaining balance
Amortization Schedule
Year Principal Interest Balance

Understanding Loan Amortization

A loan amortization schedule shows how each payment is split between principal and interest over the life of the loan. In the early years, most of your payment goes toward interest. Over time, more goes toward principal as the loan balance decreases.

The Formula

M = P × [r(1+r)^n] / [(1+r)^n – 1]

Where M = monthly payment, P = principal, r = monthly interest rate, n = number of payments

Key Insights

Front-loaded interest

Early payments are mostly interest because the loan balance is highest at the start.

Extra payments matter

Even small extra payments can significantly reduce total interest and shorten the loan term.

Rate impact

A lower interest rate can save tens of thousands in interest over the life of the loan.

15 vs 30 year

Shorter terms have higher monthly payments but much lower total interest costs.

This calculator assumes a fixed-rate loan with monthly compounding. Actual payments may vary slightly due to rounding.