Tested tool guide
Tested browser tools
Checked August 16, 2026
What Student Loan Calculator does, with a checked example
Federal student loans can be repaid on several different schedules, and this tool shows them side by side: standard, graduated, extended, and the income-driven plans that tie the payment to income and forgive whatever remains after 20 or 25 years. You enter balance, rate, income, and household size, and it returns monthly payments, payoff dates, and forgiveness timelines. The surprise for most borrowers is that an income-driven payment is set by income, not by how much you owe, so a small loan can carry a larger payment than a big one. Everything runs in the browser; your numbers never leave it.
Worked example
A concrete input and expected output from the current implementation.
Input
Loan balance $10,000, fixed interest 5.0%, Standard Repayment Plan (10-year term)
->
Expected output
Monthly payment $106.07. 120 monthly payments. Total paid about $12,728, of which about $2,728 is interest. Balance reaches zero after 120 months; no forgiveness event.
Standard repayment is a level-payment amortization: month one is $41.67 in interest plus $64.40 in principal, and the split shifts each month so the loan ends at exactly 120 payments. The payment solves the amortization formula for these inputs; 106.07 times 120 minus the $10,000 balance leaves about $2,728 in interest.