Convert Excel tool to PHP/MySQL

I have an interactive Excel tool that I created and I would now like to have it converted to a format that users could access via my blog or webpage. The tools (there are four in all, all very similar) basically consist of a large amount of data (50,000 rows x 5-10 columns) and some dropdown lists. The users select their choices from the dropdown lists, which automatically populates the results area of the spreadsheet using Excel formulas. What I am looking for is code that will replicate what I have done in Excel in a format that can be accessed through a web browser. I believe the best way to accomplish this is using PHP and MySQL. I have attached here a sample of one of the files for your convenience. Thanks in advance, Mike