今天介绍的是国外一些主流的免费的实用的英文SEO 关键字工具，会对做英文SEO的同学有点帮助。
Suggestions by CheckRankings.com
Google Suggest Scraper Tool
SEO Book Keyword Suggestion Tool
DigitalPoint Keyword Suggestion Tool
Nichebot (Classic).
NicheWatch.com
GoLexa Search Tool
Keyword Lizzard
Ontology Finder
Free Keyword Suggestion Tool
Free Keyword Discovery
OVTKeywords.com
LongTailAdWords.com
SerpArchive.com
NonBot KI Tool
Keyword Difficulty Tool
SEODigger.com
