21 Best FREE SEO Tools for On-Page Optimization

Keyword Research
Developing the right list of keywords remains a staple of SEO. The keyword selection has such a profound impact on the overall performance of a website, the keyword selection process shouldn’t rely on a single tool.
1. Wordstream
2. Keyword Eye Basic
3. YouTube Keyword Tool
4. Übersuggest
5. Anchor Text Over Optimization Tool
6. Convert Word Documents to Clean HTML
7. Copyscape
8. Xenu’s Link Sleuth
9. Robots.txt Generator
10. Robots.txt Checker
11. URI Valet
12. Title and Description Optimization Tool
13. Image SEO Tool
14. Schema Creator
15. Google Snippet Preview
16. Structured Data Testing Tool
17. XML Sitemap Generators
18. XML Sitemap Inspector
19. Pingdom Website Speed Tool
20. Fiddler
21. Microsoft Free SEO Toolkit