Usernames on CodePen allow uppercase and lowercase. For example, a combination of upper and lower case, like: http://codepen.io/SaraSoueidan/ You know what was wicked annoying? If you went to, for example: http://codepen.io/sarasoueidan/ It would fail (404). Now, it won’t. Even if you go to: http://codepen.io/SarAsOUeiDaN/ You’ll get redirected to the correct URL. HoT DigGiTY doG!