What Is a Student Loan Calculator?
A student loan calculator helps you estimate your monthly payments and total repayment cost under different federal repayment plans. By comparing Standard, Extended, and Income-Based Repayment (IBR) side by side, you can see the true long-term cost of each option and choose the plan that fits your income and goals.
How Federal Student Loan Repayment Plans Work
When you graduate or leave school, your federal loans enter a 6-month grace period. During this time, interest accrues on unsubsidized loans and capitalizes (is added to your principal) when repayment begins. After the grace period, you choose a repayment plan:
- Standard (10 years): Fixed payments over 120 months. Highest monthly payment, lowest total interest — the fastest way out of debt.
- Extended (25 years): Lower monthly payment spread over 300 months. Available if your balance exceeds $30,000. You pay significantly more interest overall.
- Income-Based Repayment (IBR): Payments are capped at 10% of discretionary income. Remaining balance may be forgiven after 20–25 years (currently taxable).
Repayment Formulas Used
M = P × [r(1+r)^n] / [(1+r)^n − 1]
P = loan balance · r = monthly rate (annual rate ÷ 12) · n = number of months
Payment = max(0, (Income − 150% × Poverty Line) × 10% ÷ 12)
2026 poverty line: $15,060 (single) + $5,380 per additional person
2026 Federal Student Loan Interest Rates
| Loan Type | Who It's For | 2026 Rate |
|---|---|---|
| Direct Subsidized | Undergraduates with financial need | 6.39% |
| Direct Unsubsidized (Undergrad) | All undergraduates | 6.39% |
| Direct Unsubsidized (Graduate) | Graduate students | 7.94% |
| Direct PLUS Loans | Graduate students & parents | 8.94% |
Frequently Asked Questions
What is Income-Based Repayment (IBR)?
IBR caps your monthly federal student loan payment at 10% of your discretionary income — the amount your income exceeds 150% of the federal poverty line for your family size. In 2026, the poverty line is $15,060 for a single person. If your income is low enough, your IBR payment can be $0. After 20–25 years of qualifying payments, any remaining balance is forgiven (though currently taxable).
What are the 2026 federal student loan interest rates?
For loans disbursed in the 2025–2026 academic year: Undergraduate Direct Subsidized/Unsubsidized loans are 6.39% fixed, Graduate Unsubsidized loans are 7.94% fixed, and Direct PLUS loans are 8.94% fixed. These rates are locked for the life of each loan.
How does Public Service Loan Forgiveness (PSLF) work?
PSLF forgives your remaining federal Direct Loan balance after 120 qualifying monthly payments (10 years) while working full-time for a qualifying employer — government agencies, 501(c)(3) nonprofits, or other qualifying nonprofits. You must be enrolled in an income-driven repayment plan. Forgiven amounts under PSLF are currently tax-free.
What is the Standard vs Extended repayment plan?
The Standard plan spreads payments over 10 years with fixed amounts — you pay the least total interest. The Extended plan stretches to 25 years, reducing your monthly payment but significantly increasing total interest paid. Extended requires a balance above $30,000 in Direct or FFEL loans.
Should I refinance my federal student loans?
Refinancing can lower your interest rate with good credit, but it converts federal loans to private loans — permanently losing access to IBR, PSLF, deferment, forbearance, and income-driven forgiveness. It makes sense only if you have stable income, won't use federal protections, and can qualify for a meaningfully lower rate.
What happens to my loans if I can't make payments?
Federal loans offer protections: Deferment pauses payments (no interest on subsidized loans), Forbearance pauses payments (interest accrues), and income-driven plans can set payments to $0. After 270 days of non-payment, loans enter default — damaging your credit and triggering collection actions.
When does student loan forgiveness happen under IBR?
Under IBR and similar income-driven plans, remaining balances are forgiven after 20 years of qualifying payments for undergraduate loans, or 25 years for graduate loans. Unlike PSLF, this forgiveness is currently treated as taxable income in the year it occurs — plan accordingly.
What is the 6-month grace period for student loans?
Most federal student loans grant a 6-month grace period after you graduate or leave school. You owe no payments during this window. However, interest keeps accruing on unsubsidized loans and capitalizes (adds to your principal) when repayment begins — this calculator models that capitalization.