Student Loan Calculator

The standard amortisation payment: A = P × r ÷ (1 − (1 + r)^−n), where r is the annual rate divided by twelve and n is the number of months.

P

Amount borrowed

r

Monthly interest rate: the annual rate divided by twelve

n

Number of monthly payments in the repayment plan

A

The level monthly payment

I

Total interest: what the payments come to, less what you borrowed

y

Repayment years: n divided by twelve

Use it the moment you are choosing between plans, and use it twice with different terms rather than once. The payment is what your budget feels every month, and it is the number people compare; the total interest is what the loan actually costs, and it is the number people skip. The gap between them is at its widest on exactly the loans that feel most affordable, because a payment stretched far enough can look small while the interest climbs past the original amount borrowed — the 25-year row in the chart below has you paying more in interest than you borrowed. Also use it before you make an extra payment: the answer to whether overpaying a student loan is worth it depends on the rate on the loan against whatever else the money could do, and this page gives you the rate side of that comparison. What it will not tell you is whether you qualify for a subsidised or income-linked plan, which is usually the larger question.

1. 30,000 at 6.5% over ten years

   1. Monthly rate: 6.5 ÷ 12 = 0.541667%, or 0.00541667 as a decimal
   2. Payment: 30,000 at 0.541667% over 120 months = 340.64 a month
   3. Paid in total: 340.64 × 120 = 40,877.41
   4. Interest: 40,877.41 − 30,000 = 10,877.41
   5. Interest per 100 borrowed: 10,877.41 ÷ 30,000 × 100 = 36.26

   The shape most people picture when they think of a student loan: ten years, a payment a little over 1% of the balance each month, and interest of about a third of what was borrowed. Check the last figure against your own plan before anything else — if your loan is 30,000 and your statement says the interest will be nearer 78 than 36 per 100, you are on a much longer term than you thought.

2. The same loan over twenty years

   1. Same balance, same rate, twice as many payments
   2. Payment: 30,000 at 0.541667% over 240 months = 223.67 a month
   3. The payment falls by 340.64 − 223.67 = 116.97 a month
   4. Paid in total: 223.67 × 240 = 53,681.74
   5. Interest: 53,681.74 − 30,000 = 23,681.74, against 10,877.41 over ten years
   6. Interest per 100 borrowed: 78.94, up from 36.26

   Doubling the term cuts the payment by about a third and more than doubles the interest — 12,804.33 more, bought with 116.97 a month of breathing room. Whether that is a good trade depends entirely on what the money does elsewhere, and that is a question this page cannot answer.

3. An 80,000 graduate balance at 6.5% over twenty-five years

   1. Payment: 80,000 at 0.541667% over 300 months = 540.17 a month
   2. Paid in total: 162,047.85, once the final payment has been adjusted to clear the balance
   3. Interest: 162,047.85 − 80,000 = 82,047.85
   4. Interest per 100 borrowed: 102.56, so the interest exceeds the amount borrowed
   5. Repayment years: 300 ÷ 12 = 25

   Interest of more than 100 per 100 borrowed. The payment still looks manageable at 540.17, which is exactly the trap: at this term the loan costs more than twice what was borrowed, and the monthly figure gives no hint of it.

This page models a single loan repaid on a level monthly payment with a fixed rate, and real student debt often is none of those things. If you have several loans — which is common, one per academic year or per programme — the correct calculation is one payment per loan added together, not one payment on the combined balance, because each loan carries its own rate and its own term; the combined figure will be close but not right. It knows nothing about subsidy, grace periods or forgiveness. While you are studying, many loans either do not accrue interest or do not require payment at all, and after you finish many systems give a grace or deferment period before repayment starts; neither is here, and both change the answer. Income-linked plans are also absent: under those the payment is a percentage of your income rather than a function of the balance, and any remaining balance may be written off after a fixed number of years, which turns the calculation into something this page cannot express. Rates that change with a policy announcement, or that are fixed to a market benchmark plus a margin, are not modelled — this page holds one rate for the whole term, so re-run it if yours moves. Finally there is no currency and no jurisdiction here: 30,000 and 6.5% mean whatever you type, and the repayment conventions of your country are not built in.

Does a longer repayment term save me money?

It lowers the payment and raises the cost, always. On 30,000 at 6.5%, moving from ten years to twenty cuts the monthly payment by 116.97 and adds 12,804.33 of interest. The only reason to take the longer term is if the lower payment is what keeps you solvent, or if you have a specific plan for the money difference that beats 6.5%.

Why is my interest more than I borrowed?

Because the term is long enough for the rate to compound past the principal. At 6.5% over twenty-five years the interest comes to about 102 per 100 borrowed, so the loan costs more than twice its face value. This is not a penalty or an error; it is what a percentage does over long periods, and it is the strongest argument for paying more than the scheduled amount when you can.

Should I pay off a student loan early?

Compare the rate on the loan against what the money would safely earn elsewhere, then weigh the things this page cannot see: some loans have forgiveness provisions that make early repayment a mistake, and some have interest subsidies that stop when you overpay. If neither applies, repaying a loan at 6.5% is a guaranteed 6.5% return, which is a high bar for a savings account.

How do I handle several loans at different rates?

Run this page once per loan and add the monthly payments. Do not average the rates and run it once on the total: the combined answer is close but wrong, because a small high-rate loan and a large low-rate loan do not behave like one medium loan at the average rate. Paying extra on whichever loan has the highest rate saves the most.

What about interest while I am still studying?

It is not modelled here, and it matters. Depending on the programme, interest may be paid for you while you study, may accrue and be added to the balance when repayment starts, or may not accrue at all. If it accrues, the balance you start repaying is larger than the amount you borrowed, and you should enter that larger figure.

Is the monthly payment the same for the whole term?

On the plan this page models, yes: one level payment for every month, which is called a standard or fixed instalment plan. Graduated plans start lower and rise on a schedule, income-linked plans track your earnings, and extended plans stretch the term for larger balances — none of those produce the level payment you see here, so do not compare this figure against them directly.

• 34 CFR 685.208 — Repayment plans: the United States federal regulation that defines the standard, graduated, extended and income-contingent plans a Direct Loan can be repaid under — Electronic Code of Federal Regulations, Office of the Federal Register (United States)
• Repaying your student loan: how repayment works in England, Wales and Northern Ireland, including the income threshold and the write-off period — GOV.UK (United Kingdom)