How do I convert a Microsoft Excel application to a web based app that others could use?

File > Save As > rename your file and then choose File Type Web Page or XML or as I use just type and rename any file by the extension .html to change such file to a webpage or to txt file and connect it to any data base management system. there are many other ways.

if you saved it by using file type web page it will be saved as a Folder Book1 and contains:

• filelist.txt  or XML File you can open it with notepad or textdocument
• sheet1 and that is your web page you can open it with any web browser because HTML document
• Stylesheet  and that is cascading style sheet to control your webpage styles and colors
• there will be other files I am not sure what are they :(

Generally, you should import the excel sheet into database(that is not much tricky if you have a bit how know with database) and when its data is in database then in web app you can use in the way whatever you want and there will be no chance to loose data ever. if need more help let me know :) 

I am sorry I don't have a website and this is a specialist Information Technology function in South Africa, the Financial Accountant would not deal with it; merely provide the data which would use lookup and pivot table functions.

What I am saying, is I don't have experience in this field.

Basm Allah Alrahman Alrahim

  Application or file ?

If you want to make application like Excel from scratch like the one at Office365 learn web Develop programming languge or cloud programming language or server side with client side programming langage

References

1 -10-best-programming-languages-2015-you-should-know

2 -10-of-the-coolest-cloud-programming-languages

3 - what-is-cloud-computing

4 - wiki books  wiki Web development Choosing the right programming language

5 - which-programming-language-for-cloud-computing

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