> For the complete documentation index, see [llms.txt](https://apidoc.ants.co.th/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://apidoc.ants.co.th/api-sms-1/preview.md).

# Preview Message

        You can check the amount of credits before actual sending SMS; this API function allows you easily calculate the total credits spending, also adjusting the message text to be aligned with cost.

### Sequence Diagram

![Sequence Diagram (API Preview)](/files/-M1yujvhuswNJ8lkfhlu)

{% tabs %}
{% tab title="Request" %}
**You can start creating HTTP request as this following:**

| Header             | Description                                                                                                |
| ------------------ | ---------------------------------------------------------------------------------------------------------- |
| HTTP Request (URL) | <https://api-service.ants.co.th/sms/preview>                                                               |
| HTTP Headers       | <p>Content-Type: application/json</p><p>Authorization: (Basic Auth) Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==</p> |
| HTTP Methods       | POST                                                                                                       |

#### :exclamation: You must input at least 1 parameter. In this case; there is only "message"

| **Parameter** | Type   | Description                                      |
| ------------- | ------ | ------------------------------------------------ |
| message       | String | tText of the message that would be used to send. |

**The request will look like**

```
{
"message": "Let's see how many characters will remain unused in this message."
}
```

{% endtab %}

{% tab title="Response" %}
**Response**&#x20;

| Parameter       | Type   | Description                                                                                            |
| --------------- | ------ | ------------------------------------------------------------------------------------------------------ |
| originalMessage | String | Original message that would like to preview                                                            |
| credit          | Number | SMS credit usage.                                                                                      |
| character       | String | How many characters are left ‘unspent’ in the message and if the message fits in one or more messages. |

**The JSON response will look like:**

```
{
"originalMessage": "Let's see how many characters will remain unused in this message.",
"credit":  "1.00",
"character": 65
}
```

{% endtab %}
{% endtabs %}


---

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