Student Loan Calculator
Calculate your monthly student loan payment, total interest, and full amortization schedule — for either a federal or a private loan.
Last updated: August 2026
Federal student loan rates are set annually by law and are the same for all borrowers with the same loan type, regardless of credit history.
—
Amortization Schedule
| Period | Payment | Principal | Interest | Balance |
|---|
Balance Over Time
Standard repayment splits each fixed payment between interest and principal, and interest takes the bigger share while the balance is still large — so the balance barely moves at first, then falls faster as more of each payment goes toward what you actually borrowed.
The Repayment Math for Student Loans
Whether the loan is federal or private, a fixed-rate loan on a set schedule is paid off by this level-payment equation:
M: the payment due each month.
P: the balance being repaid.
r: the monthly rate, meaning the annual rate divided by 12.
n: the number of payments, meaning the repayment term in years times 12.
Federal Loans Versus Private Loans
Federal loan terms come from law and from the Department of Education: the rate depends on the loan type and the year it was first disbursed, not on your credit score. Private student loans are ordinary consumer loans. Each lender sets its own rate using the borrower's or cosigner's credit and income, so two students borrowing the same amount can be offered very different terms. Federal loans also carry protections, such as multiple repayment plans, deferment options, and forgiveness programs, that private lenders are not required to match. Financial aid guidance usually recommends using federal options first for that reason.
Why Federal Rates Change Every Year but Your Loan's Rate Does Not
New federal loan rates are reset for each award year, tied to the result of a Treasury securities auction plus a fixed add-on that depends on the loan type, and subject to caps set in law. Once a loan is disbursed, its rate is fixed for the life of that loan. So borrowers who started in different years can hold loans at quite different rates, and the number to enter in the calculator is the rate printed on your own loan record. For the current year's rates, check studentaid.gov rather than relying on a figure printed on a page like this one.
Federal Repayment Plans in Plain Terms
Standard repayment spreads fixed payments over a set period, commonly 10 years, and usually costs the least interest. Graduated repayment starts with lower payments that step up over time. Extended repayment lengthens the term to reduce the monthly payment, at the cost of more interest. Income-driven plans tie the payment to your income and family size rather than to the balance, and can leave a balance unpaid at the end of the term that may later be forgiven under program rules. The specific plans on offer and their eligibility rules have changed over the years and can change again, so confirm what is available to you with your servicer.
What Happens to Interest While You Are in School
On a subsidized loan the government covers interest during school and certain deferment periods. On an unsubsidized loan interest accrues from the day the money is paid out. If you do not pay that interest as you go, it is later capitalized, meaning added to principal, so you then pay interest on a larger balance. Deferment and forbearance can pause payments, but on many loans interest still accrues during the pause, so pausing is not free unless the loan is subsidized.
Consolidation Versus Refinancing
A federal Direct Consolidation Loan combines several federal loans into one payment at a fixed rate that is the weighted average of the old rates, rounded up to the nearest eighth of a percent. It simplifies billing and can qualify you for some plans, but it rarely lowers the rate and can affect progress toward forgiveness. Refinancing through a private lender can produce a lower rate for borrowers with strong credit and income, but it turns federal loans into a private loan and gives up federal protections for good. Decide which matters more to you before comparing rates.
Worked Example
A 30,000-dollar federal student loan at 5.5% over the standard 10-year term: the monthly rate is 5.5% ÷ 12 ≈ 0.4583%, and n = 120 payments. Plugging into the formula gives a monthly payment of about 326 dollars, with roughly 9,069 dollars in total interest paid over the 10 years — for a total repayment of about 39,069 dollars on the original 30,000-dollar loan.
Student Loan Vocabulary
Principal — the amount originally borrowed, before interest is added.
Income-Driven Repayment (IDR) — a federal option that sets the monthly payment from income and family size instead of a fixed amortized amount. The main calculator uses a standard fixed payment; the Estimate Income-Driven Payment toggle above gives a rough, simplified approximation.
Grace Period — a window after you leave school, commonly six months on federal loans, before regular repayment begins.
Subsidized vs. Unsubsidized — on a subsidized federal loan the government pays interest during school and certain deferments; on an unsubsidized loan interest accrues the whole time.
Capitalization — unpaid interest being added to the principal balance, so later interest is charged on the larger total. The Grace Period / Deferment field above estimates this.
Origination Fee — a percentage deducted from each disbursement before you receive it. On federal loans the percentage is set by law, so check studentaid.gov for the current figure; private lenders set their own. Enter it above to see the cash you actually receive, while the payment is still based on the full amount borrowed.
Sources & Further Reading
- Federal Student Aid — Repayment plans: the Department of Education's description of federal repayment plans and how to choose among them.
- Federal Student Aid — Interest rates and fees: where the current federal loan rates and fees are published each year.
- Consumer Financial Protection Bureau — Student loans: consumer guidance on repaying, refinancing, and avoiding problems with student loans.
This calculator gives estimates for information only. It is not a loan offer or financial advice, and actual terms depend on your loan program, servicer, and, for private loans, your credit, so confirm exact figures with your loan servicer.
Frequently Asked Questions
What is the difference between federal and private student loans?
Federal loans have rates set by law that do not depend on your credit, plus protections such as income-driven repayment and deferment. Private loans are priced by each lender from credit and income, so identical loan amounts can carry very different rates and fewer safeguards.
Why do federal student loan rates change every year?
New rates are set for each award year using a Treasury auction result plus a loan-type add-on, within legal caps. A loan's rate is then fixed once it is disbursed, so your rate depends on the year each loan was first paid out. Check studentaid.gov for the current rates.
What repayment plans does the federal government offer?
In concept: standard (fixed payments over a set period), graduated (payments that rise over time), extended (a longer term with lower payments), and income-driven (payments based on income and family size). The exact plans available change over time, so confirm current options with your servicer.
Would an income-driven plan give me a lower payment?
The main calculator models standard fixed repayment. Checking Estimate Income-Driven Payment and entering your income and family size gives a rough estimate, based on a share of income above a multiple of the federal poverty line for your household, divided by 12. It is a simplified approximation, not a servicer calculation, but it shows whether an income-driven plan is in the right range.
Should I consolidate or refinance multiple student loans?
They are different tools. Federal Direct Consolidation combines federal loans into one payment at the weighted average rate rounded up slightly, and rarely lowers your rate. Refinancing with a private lender can lower it if your credit and income are strong, but it permanently converts federal loans to private ones and forfeits federal protections.
What is the difference between a subsidized and unsubsidized student loan?
On a subsidized federal loan the government pays interest while you are in school at least half-time and during grace and deferment, so the balance does not grow. On an unsubsidized loan interest accrues throughout and, if unpaid, is capitalized when repayment starts, which the Grace Period / Deferment field above estimates.