Model the Repayment Schedule, Not a Servicer Statement
The calculator applies the entered balance, rate and repayment period to a standard repayment model so you can see how term length and additional payments change total interest and payoff timing.
Federal income-driven plans, capitalization events, deferment, forgiveness rules, subsidies, variable private-loan terms and servicer-specific daily interest can change real repayment. Use the result as a comparison scenario rather than a prediction of a federal or private-loan account statement.
For a simple fixed-payment loan, the math is straightforward; real student-loan repayment can be much less so. Federal repayment plans can tie payments to income, private loans may use different terms, and periods of deferment or capitalization can change the balance. That is why the most useful use of this calculator is comparison: test how a different rate, term or extra principal payment changes the modeled path, then compare that with the terms shown by your servicer or lender.
Frequently Asked Questions
Will this reproduce an income-driven repayment plan?
No. Income-driven federal plans depend on program rules, income, household information and recertification details outside a simple amortization model.
What does an extra payment change?
When extra money is applied to principal, the balance used for later interest is lower, which can shorten payoff time and reduce modeled interest.
Can I use this to compare refinancing with my current student loan?
Yes for the basic payment and interest trade-off, provided you enter comparable balances, rates and terms. It will not reproduce federal protections, forgiveness rules or every lender-specific feature.
Methodology & Related Tools
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