Here is a tool that allows you to make W3C XHTML validation of an entire website !
Multipage Validator is a really handy tool for those who wish to validate all pages of a website W3C XHTML. This online service is free and is based on the official W3C validator.
The operation is very easy : enter URL of the website to validate and let’s go ! All website pages will be indexed and validated one by one to give you a full and detailed report. Note that “the time for indexing the website varies depending on page size, speed and DNS server“.
Indeed, the procedure can be quite heavy if your website contains many pages. But for a website that has about 150 separate pages, validation takes approximately 2 minutes, which is very acceptable. This service will be really useful to miss any part of your website and follow the W3C recommendations.