Two-factor authentication is critical for protecting your online accounts, but sadly, not every site supports it. TwoFactorAuth.org highlights all the sites that do or do not support two-factor authentication.
We've highlighted the most important sites where you should enable two-factor authentication before. TwoFactorAuth.org is a pretty comprehensive list across different website categories, from social networks to online shopping and cloud storage.
Developed by computer science student Josh Davis, the site is open source, so you can add websites that aren't already on the list over at GitHub.
In addition to telling you the kind of two-factor authentication supported (such as Google Auth or SMS), you'll find links to the site's security information and the ability to send a tweet to a site to tell them you want two-factor authentication.
As Davis writes on his blog post, if every site listed on TwoFactorAuth.org "ends up in the green and his website becomes pointless", it will have been a success.