Student Loan Calculator
Monthly payment and lifetime interest on a student loan.
Your figures
Result
How to use this tool
- Enter your own figures over the defaults — Loan amount, Annual interest rate, Term.
- The answer updates as you type. There is no button, and nothing is sent anywhere.
- Change Annual interest rate on its own to see how much it moves the result — the worked example below shows exactly that.
This models a standard fixed-repayment loan. Income-driven and forgiveness-linked plans work differently and cannot be modelled with a simple amortisation formula.
How it works
This takes 3 inputs — loan amount, annual interest rate, term — and returns monthly payment, total repaid, total interest, interest as share of loan and number of payments. The whole calculation happens in this page as you type: there is no submit button, no request, and nothing stored.
Because it recalculates on every keystroke you can use it as a sensitivity test rather than a one-shot answer. Moving annual interest rate alone from 6 to 7 changes monthly payment from 444.08 to 464.43 — the worked example below sets that out in full.
A worked example
Worked through with the figures the page already has in it: loan amount of 40,000 and annual interest rate of 6 %, and the rest as shown, giving monthly payment of 444.08. These numbers come from running the calculator’s own code, not from being typed in here, so they cannot drift away from what you see on screen.
Starting from:
- Loan amount: 40,000
- Annual interest rate: 6 %
- Term: 10 years
| Result | Value |
|---|---|
| Monthly payment | 444.08 |
| Total repaid | 53,289.84 |
| Total interest | 13,289.84 |
| Interest as share of loan | 33.2% |
| Number of payments | 120 |
What happens when one input moves
Holding everything else steady and changing Annual interest rate from 6 % to 7 % — one percentage point — moves the answer like this:
| Figure | 6 % | 7 % |
|---|---|---|
| Monthly payment | 444.08 | 464.43 |
| Total repaid | 53,289.84 | 55,732.07 |
| Total interest | 13,289.84 | 15,732.07 |
| Interest as share of loan | 33.2% | 39.3% |
| Number of payments | 120 | 120 |
That is usually the number worth arguing over: it is easier to move than the headline amount, and the difference compounds across the whole term.
Student Loan Calculator — frequently asked questions
Does this work for income-driven repayment?
No. IDR plans set payments as a share of discretionary income, with possible forgiveness after a set period. This calculator models standard fixed repayment.
Should I pay extra?
If the interest rate exceeds what you would earn investing, extra payments are effectively a guaranteed return. Below that, the maths favours investing — but the certainty of clearing debt has value too.
What about interest during study?
Unsubsidised loans accrue interest while you study, which is then capitalised. Enter the balance at the point repayment begins.
Is this calculator free?
Yes, with no account, no limits and no data collection. It runs entirely in your browser.
Should I rely on this for a financial or medical decision?
No. It is a planning estimate built on standard formulas and stated assumptions. For decisions that matter, speak to a qualified professional who can account for your full circumstances.
How accurate is the Student Loan figure?
The arithmetic is exact. With the defaults on this page — loan amount 40000, annual interest rate 6 %, term 10 years — it returns monthly payment of 444.08. What limits accuracy is the assumptions, not the maths: change annual interest rate to 7 % and the same formula gives 464.43. Treat it as a well-founded estimate, not a quotation.
Related tools
From other categories
Background reading: Loan, Mortgage and Investment Calculators Explained
Nothing is sent anywhere. The figures you type stay in this page and are never transmitted or stored — how that works.
Disclaimer. The formula is exact; the answer is only as good as the figures and assumptions above. Not financial, tax, medical or legal advice. Full disclaimer.