You might want to investigate HTML::TagFilter which makes this pretty easy.

Or simply use HTML::Parser, writing a handler for start/end tags and only outputting ones you want (examples are here).

Update:
If you wanted a list of valid HTML tags, you could look at HTML::Tagset and %HTML::Tagset::isKnown

gav^

In reply to Re: Finding and replacing 'nonvalid' html tags? by gav^
in thread Finding and replacing 'nonvalid' html tags? by BUU

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