A valid HTML tag starts with a < followed by the name of the tag. A / character is also allowed following the < to indicate the closing tag. Whitespace can also be used in the tag to separate tokens.

The code below finds and replaces the tag names into upper case. 

while (<>)
{
    s/(<\s*\/?\s*)(\w+)/$1\U$2/g;
    print;
}

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In reply to Re: Converting HTML tags into uppercase using Perl by inman
in thread Converting HTML tags into uppercase using Perl by steve_g50

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