Whats the way to check that how much time page take to show records ?

Whats the way to check that how much time page take to show records ?

  

I'm using a function to check whether the coming value (string) contain "Normal Text" or "Rich text". Now I want to be sure whether my approach delay the page load time or not.

I want to test how much time the page takes to show records having Rich text entries and  then after applying my function then I want to know how much time the page takes to show records having HTML entries.

Please help if anyone can guide me steps to check it.

Any help will be appreciated !


Best Regards,

Gaurav

devtools, and then timeline?