Student Loan Calculator
Estimate your student loan payment, total interest and payoff date — including interest that builds up while you are in school, the new federal Tiered Standard and RAP plans, extra payments and a plan comparison.
How it works
M = P × r ÷ (1 − (1 + r)^−n) · r = annual rate ÷ 12 · n = years × 12 · In school: interest = amount × rate × time until repayment (added to P unless paid or subsidized) · RAP: (1%–10% of AGI ÷ 12) − $50 per dependent, at least $10
In repayment, a student loan amortizes like any fixed-rate loan: P is the balance, r the monthly rate and n the number of monthly payments, and each payment covers that month’s interest before reducing the balance. If you are still in school, the calculator first projects what you will owe: each year’s borrowing collects simple interest from the start of that school year until repayment begins after the grace period. On unsubsidized federal and most private loans that interest is added to the balance (capitalized) when repayment starts, unless you pay it as it comes; on subsidized loans the government covers it. You then choose a plan. A fixed term is the classic 10-year standard plan or a private loan term. The federal Tiered Standard plan sets the term from the balance — 10, 15, 20 or 25 years. The Repayment Assistance Plan (RAP) bases the payment on income: a percentage of adjusted gross income from 1% to 10%, divided by 12, less $50 per dependent, at least $10. Under RAP, interest your payment doesn’t cover is waived, the government tops up principal reduction to the payment amount up to $50, and what remains after 30 years is forgiven. You can also enter a payment you want to make and see how long it takes. Extra payments go straight to principal. The comparison table runs the same balance through the main options.
Worked example
A $30,000 loan at 6% over 10 years costs $333.06 a month: 120 payments total $39,967, so interest is about $9,967. Under the Tiered Standard plan the same balance gets a 15-year term and a $253.16 payment, but interest rises to about $15,568. A student with two years of school left who has borrowed $30,000 and will borrow $10,000 more each year at 6% with a 6-month grace period will owe $56,900 when repayment starts, because $6,900 of unpaid interest is capitalized (simple interest: $30,000 for 30 months, $10,000 for 30 months and $10,000 for 18 months). On a 10-year term that is $631.71 a month.
Sources: U.S. Department of Education — RISE final rule fact sheet (Tiered Standard plan and RAP) · Edfinancial (federal loan servicer) — Repayment Assistance Plan · Federal Student Aid — Loan Simulator and repayment plans
Frequently asked questions
What happens to interest while I’m in school?
On unsubsidized federal loans and most private loans, interest starts building from the day the money is paid out. If you don’t pay it, it is added to your balance when repayment begins, so you pay interest on interest. Choose “Still in school” to see how much that adds, or switch to paying the interest as it comes to compare. Subsidized federal loans don’t charge you interest during school and the grace period.
What are the new federal repayment plans?
For federal Direct Loans made from July 1, 2026, borrowers choose between the Tiered Standard plan, a fixed payment over 10 to 25 years depending on the balance, and the Repayment Assistance Plan (RAP), an income-based payment of 1%–10% of AGI with $50 off per dependent and a $10 minimum. Older income-driven plans are being phased out. Check studentaid.gov or your servicer for the plans your loans qualify for.
How is the RAP payment estimated?
The calculator finds your income band, takes that percentage of your AGI (or $120 a year if AGI is $10,000 or less), divides by 12, subtracts $50 per dependent and keeps at least $10. It repeats this every year with your expected income growth, waives interest the payment doesn’t cover, adds the government’s principal match, and forgives what is left after 360 payments. Your servicer’s figure may differ, for example for married borrowers or spouses with their own loans.
Should I pay off student loans early?
Extra payments go straight to principal and cut total interest, which helps most on higher-rate private loans. Turn on extra payments under More options to see the savings. On federal loans, weigh early payoff against keeping income-based protections and possible forgiveness.
What income do I need for this payment?
A common rule of thumb is to keep student loan payments at or below about 10% of gross income. The calculator shows the yearly income at which your payment would be exactly 10%.
Does this include loan fees?
No. Federal Direct Loans deduct an origination fee (about 1.06%, or about 4.23% for PLUS loans) from each disbursement, so you receive slightly less than you borrow while owing the full amount. Enter the full amount borrowed to get the right payment.
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This is an educational estimate, not financial or tax advice. Confirm figures with a professional.