<prompt> Human: I have about 23000 in principal left. Its a combination of several smaller student loans with an average interest rate of about 6.I pay 500month on it, and on the service website my payments break down to about 380 towards principal, and about 120 towards interest. This seems wrong. Can anyone please explain the math to me?  <response>: Its dead on right.Interest accrues at your interest rate. For rough calculations, you can do principal times interest rate divided by twelve for monthly interest accrual.23,000 x .06 1380 interestyear 12 115 interestmonth 