Answer by Furqan Arshad:
I am sharing some of the best tools for analyzing website’s onsite and offsite SEO issues, positive factors and overall performance.
For Onsite SEO Check:
Screaming Frog free tool: this is great tool which gives you complete report on all the meta tags, error pages and everything your website have wrt SEO.
Spyfu: A great online tool for website backlinks and seo analysis
Ahrefs: another great onsite and offsite seo analysis tool
woorank: Great online tool for website analysis, design, seo and backlinks analysis.
Free SEOSpyglass: A great tool for almost everything related to SEO and backlinks
I am mostly using these tools so I recommend you to go for these tools.