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Loan Calculator Calculators

Monthly payment, total interest and payoff totals for any fixed-rate loan.

Loan Calculator is a free online tool that monthly payment, total interest and payoff totals for any fixed-rate loan. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.

Price
Free — no account, no quota, no watermark
Category
Calculators
Where it runs
In your browser, on your device
Files uploaded
None
Technology
plain JavaScript
Settings
5
Works offline
Yes, after the first visit

About Loan Calculator

The standard amortising formula, P × r ÷ (1 − (1 + r)^−n), where r is the monthly rate and n the number of payments. Every payment is the same size; what changes is the split between interest and principal, which starts interest-heavy and ends principal-heavy.

How to use it

  1. Enter loan amount, annual interest rate and term (months).
  2. Adjust the remaining 2 settings if the defaults do not fit your case.

The 5 settings

SettingWhat it doesDefault
Loan amountA numeric value.15000
Annual interest rateA numeric value.7.9%
Term (months)Range 1–600.60
Arrangement feeA numeric value.0
CurrencyChoose from 7: USD $, GBP £, EUR €, INR ₹, AUD A$, CAD C$….USD $

Under the hood

Runs onplain JavaScript — runs the whole thing
ControlsLoan amount, Annual interest rate, Term (months), Arrangement fee, Currency

Questions

Why does the total repaid exceed the loan by so much?

Because interest accrues on the outstanding balance for the whole term. On a five-year loan at 8% you repay roughly 22% more than you borrowed — the "cost of borrowing" figure makes that explicit.

What does the currency option change?

It offers 7 choices — USD $, GBP £, EUR € and INR ₹ and more. The default is USD $, which suits most cases; change it when your input or your destination calls for something specific.

What are the limits on term (months)?

It accepts 1 to 600, starting at 60.

Is the arithmetic exact?

It uses double-precision floating point — about 15 significant figures, far more than the inputs justify. Displayed rounding is cosmetic; the underlying numbers are not rounded between steps, so chained results do not drift.