不错的一个国外seochat网站，检测工具地址为:http://www.seochat.com/seo-tools/check-server-headers/

官方是这样介绍的：

Check server headers and verify HTTP status codes. There are seven HTTP status codes that we are primarily interested in from an indexing and search engine marketing perspective. It is recommended that you verify your URIs are returning the proper Status-Code in the Server Header.

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