If you are in template/page/html/header.phtml template file, then you can check for homepage with the following code:

if($this->getIsHomePage())

{

echo 'You are in Homepage!';

}

else

{

echo 'You are NOT in Homepage!';

}

If you are elsewhere (in any other .phtml template file or in any other .php class file) then you can use the following code:

if(Mage::getBlockSingleton('page/html_header')->getIsHomePage())

{

echo 'You are in Homepage!';

} else {

echo 'You are NOT in Homepage!';

}

Below is an alternative way to check for homepage:

$routeName = Mage::app()->getRequest()->getRouteName();

$identifier = Mage::getSingleton('cms/page')->getIdentifier();

if($routeName == 'cms' && $identifier == 'home')

{

echo 'You are in Homepage!';

}else {

echo 'You are NOT in Homepage!';

}

Hope this helps. Thanks.