Understanding the repayment calculator
This calculator answers the payment-first question: given how much you can afford each month, how long until the loan is gone? It's the natural way to plan when your budget not a fixed term sets the pace. Enter a higher payment and both the payoff time and the total interest drop, often more than the extra amount would suggest.
Every loan payment splits between interest on the current balance and principal that reduces it. Because the interest share falls as the balance shrinks, raising the payment accelerates the whole process non-linearly. Just make sure the payment comfortably exceeds one month's interest otherwise the balance never falls, which the calculator flags.
Results are estimates for education only and are not financial advice.