A loan and personal-credit calculator that shows your monthly payment, total interest, total cost of credit and representative APR for any fixed-rate, fixed-term loan. Use it to compare personal loans, car finance or HP deals before you apply — especially when arrangement fees make the headline rate misleading.
How it works
The monthly payment is the standard amortising-loan formula:
M = P · r(1+r)ⁿ ⁄ ((1+r)ⁿ − 1)
where P is the amount borrowed plus any financed fees, r is the monthly rate (annual rate ÷ 12 ÷ 100) and n is the term in months. Total repaid is the payment × n. Total interest is total repaid minus the financed amount; total cost of credit is total repaid minus the cash you actually received. When fees are present, the representative APR is found by bisection — solving for the annual rate that ties your repayments to the net cash advanced, which is why it sits above the nominal rate.
Example
Borrow £10,000 at 7.9% over 5 years with no fees:
- Monthly payment: £202
- Total repaid: about £12,120
- Total interest: about £2,120, and the representative APR equals 7.9%.
Add a £300 arrangement fee financed into the loan and the representative APR rises to roughly 9.0%, because you receive £9,700 but repay against £10,300.
| Borrowed | Rate | Term | Monthly payment | Total interest |
|---|---|---|---|---|
| £5,000 | 7.9% | 3y | £156 | £634 |
| £10,000 | 7.9% | 5y | £202 | £2,120 |
| £10,000 | 12.9% | 5y | £227 | £3,620 |
| £20,000 | 5.9% | 7y | £291 | £4,440 |
For guidance only — everything is calculated locally in your browser, nothing is uploaded.