Embedding Spreadsheets

I operate and develop a fitness website and I am looking for a simple way to embed or enable a module that will allow me to put calculations into the website for people to enter stats and for it to calculate things such as caloric content and so forth.

Right now I have tons of Excel files with all of this but am wanting to share it with clients via the web. I have a third party that has some complex options for building nutritional plans and so forth but I am looking for a solution for an easy way to incorporate calculations into a site that people can use as tools to enter data and for that data to formulate a calculation.

I have looked at widgets and other things and just am not finding anything that works well. Does anyone have any suggestions? I am not a great coding mind so ease is important!