Loan interest calculator
Enter principal, nominal annual rate and term to compare two repayment methods.
Sources and adopted values
Calculation schedule
| Value | Value | Value | Interest | Value |
|---|---|---|---|---|
| Fill in the fields above — the result is computed on this page. | ||||
How do I use this page?
- Fill in the fields in the form above — the result recomputes at once, with no page reload.
- Under the result you will find the interpretation scale, if the calculator has one: it says which range your value fell into.
- The formula we use is shown lower on this page — you can check the arithmetic yourself.
- To compute the same for another game or variant, change it in the select field — prices and pools update automatically.
Further reading
Theory — how is loan interest calculated?
Loan interest is always calculated on the current outstanding balance, regardless of the repayment method chosen. With decreasing instalments the principal falls faster than with equal instalments, so total interest paid over the term is usually lower, even though the first payments are higher. The calculator lets you compare both options for the same amount, nominal rate and term. It is worth remembering that the nominal interest rate alone does not include fees, insurance or other mandatory loan costs.
Frequently asked questions
What does the loan interest calculator include?
Equal payments keep the scheduled amount stable, while decreasing payments repay equal principal portions and start higher. The calculator compares interest under both methods.
Is this result exact?
The calculation assumes a constant nominal rate and no commission, insurance, recurring fees or day-count adjustments.