2021 NerdWallet Best-of Awards Winner for Best Student Loan Refinancing Overall
2021 NerdWallet Best-Of Awards Winner

Student Loan Interest Calculator

See how much interest you’ll pay on your student loans – both month-to-month and in total – whether you have one loan or several.

Enter Your Loan Information

Loan Balance
Your remaining student loan debt to be repaid.
Interest Rate
The amount that the lender charges in interest, expressed as a percentage.
The length of time you have to repay your student loan debt in full.



Monthly Payment


Lifetime Interest

Want a lower student loan rate and bigger savings? See which refinance rates you’re qualified for in just 2 minutes or less.

FAQs – Student Loan Interest Calculator

Interest is the amount of money paid regularly at a particular rate for the use of money borrowed from a student loan lender, or for delaying the repayment of a student loan debt. In essence, it’s the “extra” money you have to pay back the lender for the opportunity to use their money to go to college (or pay off your existing student loans by refinancing).

Interest is calculated as simple daily interest for student loans. This generally means that each day, the outstanding principal balance is multiplied by the interest rate and divided by 365 days to calculate that day’s interest amount. For example, if you have a $10,000 loan and the interest rate is 7%, one day’s interest will be: ($10,000 x 0.07) / 365 = $1.92.

Our lenders generally determine interest rates by your credit score and the type of degree you have. Your loan amount usually does not directly affect the rates offered. Your annual income is factored into DTI (debt-to-income) calculations which may impact your interest rate. If you apply with a cosigner or refinance with your spouse, our lenders use the higher credit score to calculate your interest rate and save you even more on your student loans. Remember, you can check your estimated rate offers using our Compare Rates tool at any time with no impact on your credit score.

Use Purefy’s Compare Rates tool to see student loan refinance offers from multiple top lenders — all in one place with one fast form. Quickly compare your interest rate and monthly payment options, as well as your lifetime interest savings, with no impact on your credit score.

If you have high interest federal student loans or private student loans, getting a lower rate through a student loan refinance will reduce the total interest you pay (all else being equal). With more money in your pocket, you’ll have more available funds to take care of your other financial needs and life goals — or pay off your student loans even faster.

Do you currently have a fixed interest rate with your student loans? Many private lenders offer both fixed and variable rates, which can be an attractive change for some borrowers. Unlike a fixed rate, which stays the same for the entire life of the loan, variable rates fluctuate based on the current market rates. Variable rates tend to start out lower than fixed rates, so it can be a smart decision to gain extra savings while your rate is reduced, if you’re planning to pay off your debt in the next couple of years.