> For the complete documentation index, see [llms.txt](https://docs.simptel.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.simptel.com/human-identity/authentication-service/internal-authenticators/email-based-authentication.md).

# Email-Based Authentication

#### ✅ Supported Method

* **OTP via Email**: A randomly generated one-time passcode is sent to the user’s email address. The user must enter this code to complete authentication.

***

#### 🌍 Global Availability

* **All email domains and regions are supported.**
* Domain or country restrictions are not currently configurable.

***

#### ⚙️ Configuration

| Feature                   | Description                  |
| ------------------------- | ---------------------------- |
| **Integrations Provider** | Selected email provider      |
| **OTP Length**            | Typically 6 digits or 8      |
| **Expiration time**       | Default: 1–5 minutes         |
| **Template**              | Subject + message body       |
| **FROM**                  | <noreply@authentication.com> |

***

#### ⚠️ Security Notes

* For enhanced security, especially in sensitive workflows, consider using email OTP **in combination with another factor** (e.g., password or phone).


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