Student Loan Calculator
Calculate student loan payments, interest costs, and repayment schedules.
Loan Details
Total remaining balance on your student loans
Federal loans: 5.5-7.3% typical for undergrad, 6.3-8.3% for grad
Number of years to repay the loan
Additional payment toward principal
Personal Information
Used for income-driven repayment calculations
Number of people in your household
Public Service Loan Forgiveness (PSLF)
Repayment Analysis
Current Monthly Payment
Based on selected plan
Standard Payment
10-year plan
Income-Based Payment
10% of discretionary income
Principal vs Interest
Recommended Strategy
Loan Summary
Payoff Timeline
Student Loan Tips
- • Consider income-driven plans if payments are unaffordable
- • Federal loans offer more forgiveness and protection options
- • PSLF requires 120 qualifying payments while working in public service
- • Extra payments go directly to principal and save significant interest
- • Consolidation may simplify payments but could increase rates
- • Never ignore student loans - default has serious consequences
How it works
A student loan calculator amortizes your balance over the repayment term to find the monthly payment and total interest. The standard plan uses a fixed 10-year schedule; income-driven plans instead cap the payment at a share of your discretionary income, which lowers the monthly cost but usually stretches the term and adds interest.
Standard repayment
M = P · r(1 + r)ⁿ / [(1 + r)ⁿ − 1]
- P
- total balance borrowed
- r
- monthly rate (annual rate ÷ 12)
- n
- payments (standard = 120, i.e. 10 years)
Worked example
- Balance P = $30,000 at 5.5%
- 10-year standard plan → n = 120, r ≈ 0.00458
- M = 30,000 × 0.00458 × 1.00458¹²⁰ ÷ (1.00458¹²⁰ − 1)
Payment ≈ $326/month, about $9,100 in total interest over 10 years.
Good to know
- Unpaid interest can capitalize (get added to principal) after deferment or some plan changes — then you pay interest on interest, so avoid it where you can.
- Income-driven plans lower the payment but typically increase total interest by extending the term; they're a cash-flow tool, not a savings one.
- Federal loans offer protections (forbearance, forgiveness paths) that private loans usually don't — weigh that before refinancing federal debt to a private lender.
Related Calculators
Frequently Asked Questions
How are student loan payments calculated?
Standard repayment amortizes the balance over 10 years using the usual loan formula. For example, $30,000 at 6% costs about $333 a month and roughly $10,000 in total interest over the decade.
How does interest accrue on student loans?
Most accrue daily simple interest: balance x (rate / 365) per day. Unpaid interest can capitalize — get added to principal — after deferment, forbearance, or plan changes, which raises the interest you pay going forward.
What is the difference between subsidized and unsubsidized loans?
The government pays the interest on subsidized federal loans while you're in school and during deferment; unsubsidized loans accrue interest from the day they're disbursed.
What are income-driven repayment plans?
Federal IDR plans cap payments at a percentage of your discretionary income and forgive any remaining balance after a set number of years. The available plans and terms have changed recently, so check studentaid.gov for current options.
Should I pay extra or refinance my student loans?
Extra payments applied to principal shrink total interest with no downside. Refinancing can cut the rate, but refinancing federal loans into private ones permanently forfeits federal protections like IDR, deferment, and forgiveness programs.