Loans
Student Loan Payoff Calculator
Estimate your student loan's monthly payment, payoff time, and total interest from its balance and interest rate, and see the interest saved by extra payments.
How this student loan calculator works
Enter the loan as it is today
Your remaining principal balance, the fixed interest rate, and the time left to repay it. The original loan amount and term are not needed.
See the scheduled payoff
The calculator works out the required monthly payment that repays the balance over the remaining term, and the interest and total that schedule adds up to.
Add an extra monthly payment, if you like
An amount paid every month on top of the required payment goes to principal, so the balance falls faster and less interest builds up.
Compare the payoffs
See how much sooner the loan could be paid off, how much interest that saves, and how other extra amounts compare.
How student loan payoff works
How the monthly payment is calculated
A fixed-rate loan has one required payment, worked out so the last payment clears the balance at the end of the remaining term. It depends only on the balance, the rate, and the time left, so a longer remaining term means a smaller payment and more interest.
How interest accumulates
Each month, interest is the balance still owed times the annual rate divided by 12. Early payments go mostly to interest; as the balance falls, more of each payment goes to principal.
How extra principal changes the payoff
Extra payments are modeled as additional principal payments. Every extra dollar lowers the balance, so the next month's interest is smaller and more of every later payment repays principal. The required payment stays the same; the loan simply ends sooner.
Why the final payment can be smaller
The last payment is just what is left of the balance plus that month's interest. With an extra payment it is usually smaller than the others; without one, it differs from the required payment by a few cents because payments are rounded to the cent.
Example payoff comparison
$35,000 at 6.5% with 10 years left, with different extra monthly payments. Calculated the same way as the calculator above.
| Extra monthly | Monthly amount | Payoff time | Total interest | Interest saved | Time saved |
|---|---|---|---|---|---|
| $0.00 | $397.42 | 10 years | $12,690.02 | $0.00 | None |
| $50.00 | $447.42 | 8 years, 7 months | $10,650.36 | $2,039.66 | 1 year, 5 months sooner |
| $100.00 | $497.42 | 7 years, 5 months | $9,186.11 | $3,503.91 | 2 years, 7 months sooner |
| $250.00 | $647.42 | 5 years, 5 months | $6,525.16 | $6,164.86 | 4 years, 7 months sooner |
| $500.00 | $897.42 | 3 years, 8 months | $4,423.54 | $8,266.48 | 6 years, 4 months sooner |
Every extra dollar is modeled as additional principal, so the balance falls faster and each later month accrues less interest. The required payment does not change; the loan simply ends sooner, with a smaller final payment.
Example calculation
$35,000 at 6.5% with 10 years left, with $100 extra each month. Calculated the same way as the calculator above.
The scheduled payoff
Payment equals P times r, divided by 1 minus 1 plus r to the power of negative n.
- P, the balance owed
- $35,000.00
- r, the monthly rate
- 6.5% ÷ 12
- n, the payments left
- 120
- Required payment, rounded to the cent
- $397.42
- Final payment
- $397.04
- Total interest
- $12,690.02
- Total paid
- $47,690.02
With $100 extra each month
- Planned monthly amount
- $497.42
- Payoff time
- 7 years, 5 months
- Final payment
- $413.15
- Total interest
- $9,186.11
- Total paid
- $44,186.11
- Interest saved
- $3,503.91
- Time saved
- 2 years, 7 months sooner
The last payment, payment 89, would be $413.15: just what is left of the balance and its interest. The total paid is the sum of every payment, not the monthly amount times the number of payments.
Fixed-rate loans, federal and private
This calculator models a standard fixed-rate amortizing loan: the rate stays the same, a payment is due every month, and each payment covers that month's interest before it reduces the balance.
Federal and private student loans may include repayment rules that this calculator does not model. It does not account for income-driven repayment (such as SAVE, PAYE, IBR, or ICR), Public Service Loan Forgiveness or any other forgiveness, deferment, forbearance, interest subsidies, capitalization of unpaid interest, variable interest rates, loan consolidation, or servicer-specific rules.
Your servicer's required payment can differ from the one calculated here because of fees, your repayment plan, interest capitalized in the past, or how the servicer applies payments. Your servicer can confirm how extra payments are applied to your loan.
Assumptions
- The loan is a standard fixed-rate amortizing loan. The interest rate stays the same, payments are monthly, and the first payment is one month from today.
- The required monthly payment is worked out from the balance, the rate, and the remaining term with the standard amortization formula, rounded to the nearest cent. It is not your servicer's payment, which can differ.
- Each month's interest is the balance owed × the annual rate ÷ 12, rounded to the nearest cent (halves up). The final payment is the balance left plus its interest, so it absorbs the rounding.
- Extra payments are modeled as additional principal payments: the same amount every month, from the first payment, applied to the balance after that month's interest. The required payment does not change.
- Totals are the exact sums of the payment schedule, never the monthly payment times the number of payments.
- Federal and private student loans may include repayment rules that this calculator does not model: income-driven repayment, forgiveness, deferment, forbearance, interest subsidies, capitalization, variable rates, consolidation, fees, and servicer-specific payment rules are not included.
- Results are estimates for education, based on the assumptions entered. They are not a repayment plan, a servicer's figure, or advice.
How Calcora calculates
- Every calculator explains the formula behind its result in plain language.
- Calculators are designed to run in your browser, so your inputs are not sent to Calcora.
- Results help you understand your options. They are not financial advice.
Frequently asked questions
How is a student loan payment calculated?
How much faster can extra payments pay off a student loan?
Do extra payments reduce interest?
Does this calculator include income-driven repayment?
Does this calculator include student loan forgiveness?
Can I use this calculator for private student loans?
Does Calcora store my student loan information?
Related calculators
For any other fixed-rate loan, with upfront fees, use the Loan Calculator. Repaying several debts at once? The Debt Payoff Calculator compares avalanche and snowball plans. To see every payment of a loan's schedule, use the Amortization Calculator.