What are the best free SEO tools to analyse a competitor website?

What are the best free SEO tools to analyse a competitor website?

We prefer manual audits instead of any tool!

BuzzSumo. We've talked about BuzzSumo numerous times in the past, and that's because it's awesome. ...
SEM Rush. ...
SpyFu. ...
Ahrefs' Keywords Explorer. ...
AdWords' Auction Insights. ...
Crowdsourcing Keyword Research. ...
Tag Clouds. ...
WordStream's Free Keyword Tool.

If you want free tools then I would suggest you go with Woorank!!