About the Student Loan Calculator
The Student Loan Calculator models monthly payment, total interest, payoff date, and any potential forgiveness amount across five repayment plans: Standard 10-Year, Extended 25-Year, Graduated, Income-Driven (IBR/PAYE/SAVE-style cap on discretionary income), and a Custom payment scenario. Side-by-side output lets you weigh monthly cash flow against total cost over the life of the loan and compare the value of a forgiveness path (PSLF after 120 qualifying payments) against accelerated standard repayment.
It is built for recent grads choosing a federal repayment plan during the first 6-month grace period, mid-career borrowers reconsidering after an income change, public-service workers timing PSLF, and anyone considering whether to refinance federal loans into a lower-rate private loan and what protections that forfeits.
All math runs locally in JavaScript using the standard federal repayment formulas plus published income-driven discretionary-income calculations (150% of federal poverty guideline by family size, 10–20% of remainder depending on plan). Your balance, rate, income, and family size never leave the device — no servicer lead capture, no analytics call, no cookie storing the inputs.
Income-driven plans lower monthly payment but typically increase total interest paid over the loan’s life unless forgiveness is reached. Refinancing federal loans to a private lender locks in a lower rate but permanently forfeits access to IBR/PAYE/SAVE, PSLF, federal forbearance, and rate-discharge protections — rarely the right move for anyone whose income could swing materially in the next decade. Federal repayment rules change frequently (most recently SAVE plan litigation); confirm specific plan eligibility on studentaid.gov and consult a tax professional before assuming forgiveness will be tax-free in your state.
Plan Comparison
Principal vs Interest Over Time
Multi-Loan Manager
Enter each loan separately to see optimal payoff order using avalanche vs snowball methods.
Refinancing Analyzer
Enter a refinancing offer to compare total cost against your current loan.
PSLF Tracker
Track qualifying payments toward Public Service Loan Forgiveness (120 payments required).
Student Loan Repayment Plans Compared
Federal student loan borrowers have access to several repayment plans, each with trade-offs between monthly affordability and total cost. The Standard 10-Year plan amortizes the balance over 120 fixed monthly payments and minimizes total interest paid. The Extended 25-Year plan stretches payments over 300 months, cutting the monthly amount significantly but roughly doubling total interest. Graduated plans start payments low and increase them every two years, targeting early-career borrowers who expect income growth. Income-Driven Repayment plans (IBR, PAYE, REPAYE/SAVE) cap payments at a percentage of discretionary income and forgive any remaining balance after 20 or 25 years of qualifying payments. Understanding how each option affects both your monthly budget and long-term cost is the first step toward choosing the right strategy.
How Income-Driven Repayment Is Calculated
Under Income-Based Repayment (IBR), your monthly payment equals 15 percent of the difference between your adjusted gross income and 150 percent of the federal poverty guideline for your family size, divided by 12. The poverty guideline for 2026 starts at $15,060 for a single-person household and increases by $5,380 for each additional family member. If your income is low enough that the calculated payment would be zero, you owe nothing that month but interest continues to accrue. Under newer plans like PAYE and the SAVE plan, the percentage drops to 10 percent of discretionary income for undergraduate loans, with separate rules for graduate borrowers. Each plan recertifies your income annually, so payments can rise or fall as your earnings change. The calculator on this page uses the IBR formula to estimate payments and projects the remaining balance at the forgiveness horizon to give you a realistic picture of what income-driven repayment truly costs.
Student Loan Forgiveness: What Gets Forgiven (and Taxed)
After 20 years of qualifying payments (undergraduate loans) or 25 years (graduate loans), any remaining balance on an income-driven plan is forgiven. This forgiveness is not free money — the IRS currently treats the forgiven amount as taxable income in the year it is discharged. A borrower who has $40,000 forgiven while earning $60,000 that year would report $100,000 in adjusted gross income, potentially pushing them into a higher tax bracket and creating a five-figure tax bill. The SAVE plan temporarily offered tax-free forgiveness for small balances, and PSLF forgiveness is always tax-free, but standard IDR forgiveness remains taxable under current law. When comparing repayment strategies, always factor in the potential tax liability to understand the true cost of forgiveness versus simply paying the loan off on the standard timeline.
Snowball vs Avalanche: Paying Off Multiple Student Loans
Borrowers with several student loans face a sequencing decision. The avalanche method targets the loan with the highest interest rate first while making minimum payments on everything else, minimizing total interest paid. The snowball method targets the smallest balance first, generating quick psychological wins that keep motivation high. Mathematically, avalanche always wins on total cost, but behavioural research shows that borrowers using snowball are more likely to stay on track and finish paying off all their debt. The optimal approach depends on discipline: if you can stay motivated on your own, avalanche saves money; if you need visible progress, snowball gets you there. Subscribers can use the multi-loan manager above to model both strategies with their actual loan portfolio and see the exact dollar difference.
Should You Refinance Your Student Loans?
Refinancing replaces one or more existing loans with a new private loan at a different rate and term. It makes sense when you can secure a meaningfully lower interest rate and do not need access to federal benefits like income-driven repayment, PSLF, or deferment. Refinancing federal loans into a private loan permanently eliminates eligibility for those programs, so the savings must be large enough to justify that trade-off. A good rule of thumb: if your current rate is above 6 percent and you qualify for a private rate below 5 percent with a similar or shorter term, the math usually favours refinancing — provided your income is stable and you have an emergency fund. Use the refinancing analyzer above (subscribers only) to compare your current total cost against a refinanced scenario and make the decision with real numbers.
Looking for related tools? Try our Debt Payoff Calculator to tackle all your debts, or explore all Personal Finance tools.
Frequently Asked Questions
What is the Standard 10-Year Repayment Plan?
Standard 10-Year spreads the balance across 120 fixed monthly payments. It minimizes total interest paid and is the default plan for federal student loans unless another plan is selected.
What is an income-driven repayment plan?
Income-driven plans, including IBR, PAYE, and SAVE, cap monthly payments at a percentage of discretionary income and forgive any remaining balance after 20 or 25 years of qualifying payments. They lower monthly cost but often increase total interest.
Is student loan forgiveness taxable?
Forgiveness under Public Service Loan Forgiveness is generally not taxable at the federal level. Forgiveness through income-driven plans has historically been taxable as ordinary income, though temporary federal provisions have changed this for some borrowers. Tax treatment can change, so a tax professional should be consulted.
Should student loans be refinanced?
Refinancing federal loans into a private loan can lower the interest rate for strong credit profiles, but it eliminates access to income-driven plans, forbearance options, and forgiveness programs. Refinancing usually makes most sense for borrowers with stable incomes who do not expect to need federal protections.
Does paying extra on student loans save money?
Extra payments applied to principal reduce the balance and the interest accruing against it, shortening the payoff timeline and cutting total interest. Borrowers should confirm that extra amounts are applied to principal and not advanced to future payments.