Load a variable displayed in devel
Are you operating on the user account object?

If so, it should be:

$variables['account']['user']-&gt;created;


Which would be used at the template_preprocess function level. From the actual template itself, unless you have intimate knowledge of what was passed to $variables, you will sit there and guess all day long and not get far. Even I am guessing. The only way to know exactly what you have to work with is by using a real debugger.

The best option is implementing a debugger like xdebug so you can get a better idea of whats going on.


Atom has a package: https://atom.io/packages/php-debug 
PHPStorm is
simple to setup: https://www.youtube.com/watch?v=jkv0dzW3IM4


It will save a lot of time if you leverage it over devel. You can then set a breakpoint in your template_preprocess function in template.php, inspect all the variables being passed to that appropriate template, and print or modify as you need.