What are the free SEO tools for business?

Search engine optimization is more important today than ever before. If you’re looking to get started with SEO or want to achieve better results with minimal financial investment, here I am going to enlist some best free SEO tools to use.
1. Google Analytics: It is an invaluable resource that is virtually indispensable to any digital marketer serious about SEO. It shows you a lot of handy data about websites such as the number of site visits, traffic sources, and location demographics. With the help of Google Analytics, digital marketers can tweak their content strategy and figure out what works to do and what not to do. 
2. MozBar: It provides easy access to advanced metrics on webpages and SERPs. With MozBar, you can easily access the Page and Domain Authority scores of any page or site. You can also find keywords on the page you’re viewing, highlight and differentiate links, and compare the link metrics of different sites in SERPs.
3. Answer the Public: It is a nifty tool that provides content marketers with valuable data about the questions people ask online. Once you input a keyword, it fetches popular queries based on that keyword and generates a cool graphic with the questions and phrases people use when they search for that keyword.
4. SEMrush: It provides detailed information about those keywords including their position in SERPs, the URLs to which they drive traffic and the traffic trends over the past 12 months. With this feature packed tool, you can easily find out what keywords your competitors are ranking for and craft great content around those terms and phrases.