# Automatic emails to users signing in with an unrecognized devices

Offer your users more peace of mind with email notifications for sign-ins from unfamiliar devices. This feature helps users identify potentially malicious activity and take action, such as revoking suspicious sessions.

### How It Works

When a user signs in from an unrecognized device, Clerk sends an email notification to the account owner. The email includes essential details about the sign-in device, such as:

- Device type
- Operating system
- IP address
- Location
- Sign-in method

Like all emails delivered by Clerk, you can customize the template in the [Clerk Dashboard](https://dashboard.clerk.com/last-active?path=customization/email). And for supported instances, the email may also include a button to sign out from the unrecognized device immediately.

### Get Started

New device sign-in emails are enabled by default for all new applications but are disabled by default for existing instances.

For more information, visit the [Unauthorized Sign-In](https://clerk.com/docs/security/unauthorized-sign-in.md) reference page in our docs.