This plugin hasn’t been updated in over 2 years. It may no longer be maintained or supported and may have compatibility issues when used with more recent versions of WordPress.

This plugin has been closed and is no longer available for download.

Two-Factor Authentication – Clockwork SMS


Controls access to your WordPress administration panel by sending a code to your mobile phone when you try and login. Configurable for different user groups with a variety of options.

You need a Clockwork SMS account and some Clockwork credit to use this plugin.



  • Settings for Clockwork two-factor authentication

  • Prompting for a password on login to the Administration panel

  • Not allowing access if you haven't set a mobile number

  • Not allowing access if you have entered an incorrect code


  1. Upload the ‘clockwork-two-factor-authentication’ directory to the ‘/wp-content/plugins/’ directory
  2. Activate the plugin through the ‘Plugins’ menu in WordPress
  3. Enter your Clockwork API key in the ‘Clockwork Options’ page under ‘Clockwork SMS’
  4. Set your options for Two-Factor Authentication


What is a Clockwork API key?

To send SMS you will need to sign up for a Clockwork SMS account
and purchase some SMS credit. When you sign up you’ll be given an API key.

Can I send to multiple mobile numbers?

Yes, separate each mobile number with a comma.

What format should the mobile number be in?

All mobile numbers should be entered in international format without a
leading + symbol or international dialling prefix.

For example a UK number should be entered 447123456789, and a Republic
of Ireland number would be entered 353870123456.

How do I disable the plugin?

You can always override the plugin settings by setting CLOCKWORK_TWOFACTOR to false in your wp-config.php file.

Contributors & Developers

“Two-Factor Authentication – Clockwork SMS” is open source software. The following people have contributed to this plugin.




  • Small coding stardards fix
  • Tested with WordPress 4
  • Clarify License (MIT)


  • Fix form styling for WordPress 3.9


  • WordPress 3.8 compatibility.


  • Initial release.