There are two ways to get Current Category Level in Magento:
1) For category view page, use the following code snippet to get the current category level:
<?php $level= $this->getCurrentCategory()->getLevel(); ?>
2) For other pages, use the following code snippet to get the current category level:
<?php $currentCategoryObj = Mage::registry(‘current_category’); ?>
<?php $level = $currentCategoryObj->getLevel(); ?>