网页关键词密度检测

http://tool.chinaz.com/Tools/Density.aspx

360关键词挖掘

http://s.tool.chinaz.com/haosou/words.aspx

长尾词生成

http://stool.chinaz.com/longkeywords

百度关键词挖掘

http://stool.chinaz.com/baidu/words.aspx