1. Ranktank.org – this is a website that i use almost everyday in my work. it has over 30 free tools to use for basically everything SEO related.
2. Keyword Suggestion – Automatically suggest keyword strings based on a single keyword
3. Sitemap Reports – Easily create a sitemap that you can upload to Google Webmaster Tools.
4. Find Broken Links – This is a tool which combs through your whole site and highlights a number of link insights, including the internal and external links that need fixing.
5. Backlinks Checker – shows you referring pages and inbound links to your website. although you only can use this for 1 search per day if you have a VPN you can use it as many times as you want!
6. SERP Rank Checker – Tool which allows you to check different keywords on your website or blog and see its rank.
7. Traffic Tracker – Allows you to track and compare traffic on your website to other websites. A great tool tool for competitor research.
8. Google Page-speed Insights – test your webpage for the loading time and performance for desktop and for mobile and identify opportunities to improve your sites speed.
9. Google Analytics – Track Visitors to your website. and much more!
10. Backlinkwatch – Another Free tool to easily track backlinks.
11. Serpfox – A free Keyword checker to see which position you are on google on almost every country.
12. Moz Local Listing Score – See how your local business looks online
13. Google Trends – Google Trends can show you the hockey-stick rise of potential terms and SEO opportunities for your content.
14. QuickSprout Website Analyzer – a comprehensive look at just about everything: SEO optimization, speed, tags, keywords, social, links, and even competitor comparisons.
15. Schema Creator – Create custom code so that your reviews, events, organizations, and people are displayed the way you want on search pages.
16. SimilarWeb – Use this tool to compare traffic between two websites, a helpful tool for competitor research.
17. XML Sitemaps – XML Sitemaps will create a sitemap that you can upload to Google Webmaster Tools.
18. Find Broken Links – combs through your whole site and highlights a number of link insights, including the internal and external links that need fixing.
19. Structured Data Testing Tool – Structured data helps to provide context to the information on your page. This tool from Google uses live data to validate the structured data for any web page, or you can copy/paste code to test it.
20. Disavow.it – Disavow turns your list of spam URLs into a Google-ready disavow file.
21. Disavow Blacklist – This site will let you know if the domain is on a comprehensive list of spam websites.
22. Quick URL Opener – opens big lists of URLs at once. (useful for link building)
23. Panguin Tool – This tool will help your target Panda, Penguin or another Google penalty.