Calculate monthly loan payments, total interest, and repayment timelines. Part of the DevTools Surf developer suite. Browse more tools in the Calculators collection.
Use Cases
Compare total cost of standard 10-year repayment vs. extended 20-year plan for a given loan balance.
Calculate how much faster aggressive extra payments eliminate debt.
Determine the break-even point for refinancing federal loans to a lower private rate.
Model income-driven repayment (IDR) vs. standard repayment under different income scenarios.
Tips
Calculate the true cost of a loan (total interest paid, not just monthly payment) before comparing repayment plans — the standard 10-year plan pays less interest than income-driven plans over the same period.
Account for tax deductibility: US student loan interest (up to $2,500/year) is deductible for incomes below the phase-out threshold, reducing effective interest rate by your marginal tax rate.
Model extra payment impact: an extra $100/month on a $30,000 loan at 6.5% saves approximately $4,200 in interest and 2.5 years of repayment.
Fun Facts
Total US student loan debt reached $1.77 trillion in 2023, spread across approximately 44 million borrowers. The average balance for a bachelor's degree graduate is approximately $30,000.
The modern US student loan system was created by the Higher Education Act of 1965 under President Lyndon Johnson. The first federal student loans were disbursed in 1958 under the National Defense Education Act.
The Public Service Loan Forgiveness (PSLF) program was created in 2007 and cancels remaining debt after 10 years of qualifying payments — but only 2.7% of initial applicants were approved, due to complex requirements.
FAQ
Should I refinance federal student loans?
Only if you do not need federal benefits (income-driven repayment, PSLF, deferment/forbearance). Refinancing to a private loan permanently removes access to these programs. The interest rate savings must be weighed against lost protections.
What is capitalized interest?
Unpaid interest that is added to the principal balance. After capitalization, you pay interest on the interest. Capitalization occurs when a deferment or forbearance period ends on unsubsidized loans.
