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Amortization calculator

See the full payment-by-payment breakdown of a loan — exactly how much of each payment goes toward interest versus principal, and how your balance shrinks over time.

$0.00
Monthly payment
Total number of payments
Total interest paid
Total amount paid

What amortization means

Amortization is simply the process of paying off a loan through regular, equal payments over time. What makes it interesting is that the split between interest and principal shifts with every single payment: early on, most of your payment goes toward interest because the balance is still large, and only a small sliver chips away at what you actually owe. As the balance shrinks, less interest accrues each month, so more of each fixed payment goes toward principal — even though the payment amount itself never changes.

Why this matters for borrowers

Understanding amortization explains why paying off a loan feels slow at first and speeds up later. It's also why making extra principal payments early in a loan's life saves far more interest than making the same extra payment near the end — you're cutting down the balance while it's still generating the most interest.

How this calculator builds the schedule

The calculator first works out your fixed monthly payment using the standard loan payment formula, then walks through the loan month by month: each period, interest is calculated on the remaining balance, that interest is subtracted from the fixed payment to find the principal portion, and the balance is reduced accordingly. This repeats until the balance reaches zero, which — because of how the formula is built — happens exactly on the final scheduled payment.

Reading the schedule

ColumnWhat it shows
InterestPortion of that payment that covers accrued interest
PrincipalPortion that actually reduces what you owe
BalanceWhat's left to pay after that payment is applied

Switch to the annual summary view for a shorter, year-by-year total if the full monthly table feels like too much detail — useful for a quick look at how much principal and interest you'd pay in any given year of the loan.