There is no doubt for me that SEMRush proviedes the most comprehensive set of SEO tools. Almost all areas of SEO are covered, KPIs are tracked, advice given and recommendations made.  It's expensive but very good.
https://www.semrush.com/ 

There are plenty of SEO tools available that cover different areas of SEO such as keyword analysis, site checker, link building, competition spying, local listing and SEO-friendly content ideas. It really depends on what you need to do with your SEO. Some tools are all-encompassing while some only offer one area of SEO. 
 
But here’s a list of the top or best SEO tools out there.
 

• Google’s full suite of products – this is the granddaddy of SEO and they offer a whole host of software and apps to help your SEO. All of them are free. Google Analytics help analyse your site traffic and user behaviour. Google Ads’ keyword planner tool is great for keyword research and analysis. Google Trends is another that analyses search trends and you can filter based on countries, duration and others. Google Search Console is a webmaster tool that highlights SEO issues on your site as well as monitor organic keywords.
• SEMRush – you need to pay for this if you want to unleash its full potential. SEMRush is a really good all-in-one tool that helps with site audits, improving your site’s SEO and content, spying on your competitors, keyword research, link building and generating SEO friendly content ideas.
• Moz – this is another all-in-one solution and they have been around for a long time.
• Afrefs – Ahrefs is another big name for SEO tools. They offer the complete SEO solution and their link building and off-site SEO solution is claimed to be one of the best.
• KWFinder – A wonderful and easier to use alternative to Google’s free Keyword Planner. Get long-tail keywords and ideas for your keyword research.
• WooRank – easy tool to analyse your site and other site’s performance and ranking
• Yoast SEO plugin – this is one of the best tools if your website uses WordPress. Manage your on-site SEO in an all-in-one plugin.
• Answer The Public and Buzzsumo – these two are for generating content ideas and for expanding your keyword research. Answer The Public which is free gives you related terms to a keyword to create SEO friendly content, while BuzzSumo also shows you the top performing content based on keywords.