//Mage_Core_Model_Layout model
$layout = Mage::getSingleton('core/layout');

//Get handles array with Mage_Core_Model_Layout_Update model
$handles = $layout->getUpdate()->getHandles();

//Log the handles
Mage::log('Layout handles: '.print_r($handles, true));

Snippet for getting the layout handles in Magento on each request, helpful for front-end developers.

Log down all loaded layout handles in Magento on each request

php, xml, layout, magento

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