The easiest thing to do would be to use lc on $mystr like so: 

  my $index = index( lc( $mystr ), "a" );
Edited by Russ: Combined posts by ambiguous, tektsu, kilinrax, ariels, and tenatious into one

In reply to Re: How can I find the first position of a substring case-insensitively? by eg
in thread How can I find the first position of a substring case-insensitively? by ChilliHead

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