Hi,
I understood your needs. I have checked the reference website and i will provide you full functional calculator design and will provide you quality work.
I have exhaustive experience of more than 6 years with design and creation of applications using PHP,HTML5, XHTML,CSS, Javascript, Ajax, MySQL, MSSQL, and all standard database platforms,eCommerce platforms like magento,bigcommerce, Content Management Systems using CakePHP,Wordpress,Laravel,Codeigniter and others.
Awaiting for your reply.
Thanks,
Dilip :)