There is wide range of free and paid Search Engine Optimization tools available. Some most popular tools are listed below sorted according by category.

1. Free Firefox Extensions:

1. SEO Toolbar – Competitive and search data directly inserted in results obtained by searching.
2. Rank Checker – It tracks rankings easily and automatically on all important search engines.

2. Free Web based SEO Tools:

1. Keyword Suggestion Tools – By this tool, you can get keyword suggestions and the detailed statistics.
2. Keyword List Generator – This tool is used to compare keyword lists against each other.
3. Keyword List Cleaner – It simply cleans your keyword lists.
4. Meta tag Generator – It generates Meta tags for your web page.
5. Server Header Checker – It verifies that your server is sending the correct headers or not.
6. Link Suggestion Tool – It suggests keywords to search for to find relevant link sources.
7. Spider Test Tool – By this tool you can view your web page like a search engine spider.
8. Keyword Density Analyzer – It analyzes the keyword density of your page as well as competing pages.
9. Page Comparison Tool – It compares your page with competing pages to find keywords.
10. Ad Group Generator – Generates ad groups to upload to AdWords and AdCenter.

3. Premium Firefox Extensions:

1. Website Health Check – It quickly checks for many common SEO issues.
2. Duplicate Content Checker – Find pages that contain sentences matching your content.

4. Premium SEO Tools:

1. Local Rank – Links to top ranked Google pages from other top ranked results.
2. Hub Finder – It finds pages that link to competing sites which are likely to link to your site.
3. Competitive Research – It is used to find out where your competitor’s are succeeding in search.
4. Domain Name Finder – It gets keyword suggestions and finds associated domain names.
5. SEO site Planner – Plan out your SEO strategy from beginning to end.
6. Keyword List Comparison – Use this tool to compare keyword lists against each other.

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