use Benchmark; $var = '\a\\aa\\\aaa\\\\aaaa'x100; print "s: "; timethis(100000, '$var =~ s/\\\//g'); # 3 \ for benchmark print "tr: "; timethis(100000, '$var =~ tr/\\\//d'); #### s: timethis 100000: 1 wallclock secs ( 0.51 usr + 0.00 sys = 0.51 CPU) @ 195694.72/s (n=100000) tr: timethis 100000: 2 wallclock secs ( 1.68 usr + 0.00 sys = 1.68 CPU) @ 59453.03/s (n=100000) #### $var =~ tr /ab/cd/; # and $var =~ s /ab/cd/g;