> ## Documentation Index
> Fetch the complete documentation index at: https://formbnb.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Special Fields

> Control form behavior with special field names

Special fields start with `_` and control form behavior. They are not stored in submission data.

## `_next` - Redirect URL

Redirect users after successful submission:

```html theme={null}
<input type="hidden" name="_next" value="https://yoursite.com/thanks">
```

This overrides the redirect URL set in form settings.

## `_subject` - Email Subject

Customize the notification email subject:

```html theme={null}
<input type="hidden" name="_subject" value="New inquiry from website">
```

### With Variables

Include form data in the subject:

```html theme={null}
<input type="hidden" name="_subject" value="Contact from {{ name }}">
```

## `_replyto` - Reply-To Address

Set the Reply-To header for notification emails:

```html theme={null}
<input type="hidden" name="_replyto" value="user@example.com">
```

Or use a form field:

```html theme={null}
<input type="email" name="_replyto" placeholder="Your email" required>
```

<Note>
  If you have a field named `email`, it's automatically used as Reply-To. Use `_replyto` to override this.
</Note>

## `_gotcha` - Honeypot

Built-in honeypot field for spam protection:

```html theme={null}
<input type="text" name="_gotcha" style="display:none" tabindex="-1" autocomplete="off">
```

If this field has a value, the submission is marked as spam.

## `_cc` - Carbon Copy

Send a copy of the notification to additional emails:

```html theme={null}
<input type="hidden" name="_cc" value="manager@company.com,team@company.com">
```

## Example: Complete Form

```html theme={null}
<form action="https://api.formbnb.com/f/YOUR_ORG/YOUR_FORM" method="POST">
  <!-- Special fields -->
  <input type="hidden" name="_next" value="https://yoursite.com/thanks">
  <input type="hidden" name="_subject" value="New contact from {{ name }}">
  <input type="text" name="_gotcha" style="display:none" tabindex="-1">
  
  <!-- Regular fields -->
  <input type="text" name="name" placeholder="Name" required>
  <input type="email" name="email" placeholder="Email" required>
  <textarea name="message" placeholder="Message" required></textarea>
  
  <button type="submit">Send</button>
</form>
```

## Field Reference

| Field      | Type    | Description                                |
| ---------- | ------- | ------------------------------------------ |
| `_next`    | URL     | Redirect URL after submission              |
| `_subject` | String  | Email subject (supports `{{ variables }}`) |
| `_replyto` | Email   | Reply-To address for notifications         |
| `_gotcha`  | String  | Honeypot field (should be empty)           |
| `_cc`      | Emails  | Additional notification recipients         |
| `_optin`   | Boolean | Marketing opt-in flag                      |

## Notes

* Special fields are **not stored** in submission data
* They only affect form behavior
* Field names are case-sensitive
* You can use hidden inputs or regular inputs