Enter your actual monthly payment to estimate payoff timing.
Daily student loan interest calculator.
See the amount your balance adds each day, then check whether your payment is actually moving the loan toward payoff.
Daily interest
Daily interest result
$8.01/day
On a $45,000 balance at 6.50%, the loan adds about $8.01 of interest each day.
Balance$45kAPR6.50%30 days$240.41
Monthly interest$243.75estimated amount added each month
Payment vs interestNot enteredEnter payment to compare with $243.75/mo interest
Payoff projection
Payoff is secondary, but it should still be useful.
Enter your monthly payment to estimate payoff timing and compare extra payments.
Enter a payment first, then add extra money to compare savings.
Assumptions
What this estimate includes.
- Simple daily interest estimate.
- 365-day year.
- Fixed APR and fixed monthly payment.
- No capitalization events, fees, subsidies, deferment, forbearance, default charges, or IDR unpaid-interest rules.
- Use your actual servicer or StudentAid.gov rate when available.
This is planning math, not a servicer payoff quote. Confirm exact interest, payoff amounts, and payment timing with your loan servicer before making a payment decision.
FAQ
Common questions about daily interest.
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Multiply the current balance by the annual interest rate, then divide by 365. A $45,000 balance at 6.50% adds about $8.01 of interest per day.
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The 30-day number is daily interest multiplied by 30. Monthly interest uses the annual rate divided by 12, which is a slightly different estimate because calendar months are not all 30 days.
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It compares the monthly payment you enter with the estimated interest added each month. A positive number means the payment is above estimated monthly interest. A negative number means the payment is below estimated monthly interest.
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It gives a warning sign, not a legal or servicer determination. If the payment is below monthly interest, the loan may not be moving down, but capitalization, subsidies, forbearance, and repayment-plan rules can change what happens to unpaid interest.
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No. A servicer payoff quote may include interest through a specific payoff date, payment timing, fees, capitalization, and other account details. Use this calculator for planning math, then confirm exact payoff numbers with the servicer.
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