---
title: "DCA Car Finance Calculator"
canonical: "https://carfinancerefundletter.co.uk/calculator"
---
# Free DCA car finance compensation calculator (UK)

Estimates illustrative overpaid interest using amount financed, APR, loan term, and agreement start date. Adds a simple statutory-interest-style component for context. **Not** a binding FCA or lender figure.

**Canonical:** [https://carfinancerefundletter.co.uk/calculator](https://carfinancerefundletter.co.uk/calculator)

## Inputs

- Amount financed (£)
- APR (%)
- Agreement start (month/year, scheme-relevant window)
- Term (years)

## Outputs

- Estimated refund (illustrative)
- Breakdown: interest vs fair-rate benchmark, statutory interest segment

## Programmatic use

Agents can call the public JSON endpoint:

```http
POST https://carfinancerefundletter.co.uk/api/calculate-dca-refund
Content-Type: application/json

{
  "amountFinanced": 15000,
  "aprPaid": 9.9,
  "loanTermYears": 4,
  "agreementStartDate": "2018-06-01",
  "fairRate": 4
}
```

See [OpenAPI](https://carfinancerefundletter.co.uk/openapi.json) for schema, examples, and error format.

## Next step

[Open calculator in browser](https://carfinancerefundletter.co.uk/calculator) · [Generate letter](https://carfinancerefundletter.co.uk/letter)

## Disclaimer

Educational estimate only; your lender or the statutory scheme determines final redress.