> ## Documentation Index
> Fetch the complete documentation index at: https://nayax-44d6e37b-docs-marshall-faq-redistribution.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# authorize

> Initiate a financial pre-authorization on a previously detected payment method.

The `authorize` method places a financial hold (pre-authorization) on a previously identified card. This represents the second phase of a two-step transaction, occurring after a successful `cardDetect` call.

Use this method to:

* Guarantee payment by reserving a maximum dollar amount before the fueling session begins.
* Verify card validity and fund availability before the pump is activated.
* Capture a final amount that is less than or equal to the initial hold.

Example of the authorization prompt on a Nayax device:

<img src="https://mintcdn.com/nayax-44d6e37b-docs-marshall-faq-redistribution/97AxTUwdTqLzbB-t/images/approved.png?fit=max&auto=format&n=97AxTUwdTqLzbB-t&q=85&s=b2733276c9460a158fd255ade1030663" alt="Authorize" width="288" height="512" data-path="images/approved.png" />

## Requests

This command relies on the card data stored in the terminal's session buffer from the preceding detection phase. A `data` object is not required, but optional fields can be included to pass product and user context to the terminal.

The following example shows a minimal request:

```json theme={null}
{
"command": "authorize",
"requestId": "req-002"
}
```

The following example shows a request with optional data fields:

```json theme={null}
{
"command": "authorize",
"requestId": "req-002",
"data": {
"products": ["Diesel", "Unleaded", "CNG"],
"userData": ["NYX-1234", "932747"]
}
}
```

### Parameter Definitions

The table below describes the fields for the authorization request:

| Name          | Type             | Required | Description                                                                                      |
| :------------ | :--------------- | :------- | :----------------------------------------------------------------------------------------------- |
| **command**   | string           | Yes      | Set to `"authorize"`.                                                                            |
| **requestId** | string           | Yes      | A unique identifier for tracking the response.                                                   |
| **products**  | array of strings | No       | List of allowed product names (e.g., `["Diesel", "Unleaded"]`).                                  |
| **userData**  | array of strings | No       | Arbitrary user data to associate with the transaction, such as plate number or odometer reading. |

## Responses

The terminal returns a response after communicating with the financial gateway. A successful response contains the `transactionId`, which is mandatory for the subsequent settlement.

The following example shows a typical response:

```json theme={null}
{
"requestId": "req-002",
"data": {
"transactionId": "TXN-20260113-003000",
"authorizedAmount": 50000,
"state": "AUTHORIZED",
"cardBrand": "MASTERCARD",
"cardEntryMode": "CHIP",
"maskedPan": "************5678",
"aid": "A0000000031010"
}
}
```

### Response Parameters

Below are the parameters returned in the `data` object upon a successful authorization:

| Name                 | Type    | Description                                                                           |
| :------------------- | :------ | :------------------------------------------------------------------------------------ |
| **transactionId**    | string  | The unique ID for this authorized hold. **Save this value** for the `settle` command. |
| **authorizedAmount** | integer | The exact amount approved and held by the bank (refer to `decimalPlace`).             |
| **state**            | string  | Returns `AUTHORIZED` upon success.                                                    |
| **cardBrand**        | string  | The brand of the card used (e.g., MASTERCARD).                                        |
| **cardEntryMode**    | string  | The method used to read the card (e.g., CHIP).                                        |
| **maskedPan**        | string  | The masked card number for logging and receipt printing.                              |
| **aid**              | string  | The Application Identifier for the EMV transaction.                                   |