how to calculate text/code ration?

how to calculate text/code ration?

Google have tool

you should use the seoquack for calculate the text and html ration

You can use this SEO quick tool for calculating the text and HTML ration.

is it necessary to maintain text/code ration?

A page's text to code ratio is a measure of the quantity of content compared to the structure. For example, assume your page is 1,000 bytes. If 700 bytes are used for HTML tags and embedded CSS or JavaScript, 300 bytes would be readable content. You would have a text ratio of 3:7 or percentage of 30%.