SEO notes (6): SEO tools

检查首页关键词密度: http://www.ranks.nl/tools/spider.html
两个Firefox插件Search Status 和backlink checker 可以帮助你分析外链

1) http://www.0755seo.info/english-seo-tools/

2) http://tools.seobook.com/keyword-tools/seobook/

3) http://www.seobook.com/download-your-free-seo-tools/