SEMrush is a premium version that you can use for an SEO audit. It crawls the entire website and will present a detailed audit report. No matter how many pages you have on the website. It will show all duplicate content of your website and according to that your rank will go down of you have duplication. It shows accurate result as compare to other SEO Audit tools.

I have written a detailed article on Semrush, How it works and its features:- https://bit.ly/2I6oKTn