i had put cost price of product now i want to change price of product based on some multiplication like 2.5, 3 for all products.
How can i do it via magento admin or some custom code , is that possible to do change at one place in admin
Your question,is not clear in mind.
But may be your want to increase your current product price 2.5 ,3 times.
So in this case,Better idea to export current products price,sku in csv sheet from System>Import/Export section then increase those by 2.5,3 ,and Import that update sheet.
Get Product collection and update product by logic:
$collection=Mage::getResourceModel('catalog/product_collection'); foreach($collection as $product): $CurrntPrice=$product->getPrice(); // Due some logic $tempPrice=2.5*$CurrntPrice // below code use for time format $product->setPrice($tempPrice); $product->getResource()->saveAttribute($product, 'price'); endforeach;