Repayment plans / Student loan calculator
Last verified Oct 17, 2026
Student loan calculator: monthly payment and total interest
For a fixed payment over a set term. For payments based on income, use the RAP vs IBR calculator.
Year by year
Interest here is balance × rate ÷ 12 each month; servicers charge interest daily, so real figures can differ slightly. Federal loans can be paid off early with no penalty: see the payoff calculator.
How a fixed student loan payment works
Each month, interest is the balance times the yearly rate divided by 12. Your payment covers that month’s interest first, then the rest lowers the balance. Early on, more of each payment goes to interest; near the end, almost all goes to principal. A longer term means a smaller payment and more total interest.
Tiered Standard terms depend on the total principal when you enter the plan: under $25,000 is 10 years, $25,000 to under $50,000 is 15, $50,000 to under $100,000 is 20, and $100,000 or more is 25 (34 CFR 685.208). Fixed federal plans charge at least $50 a month.