If you feel comfortable with JavaScript, just save that online version and edit it to get rid of that 24 fret limitation.
If you're comfortable with perl, I have this script that I use:
#!/usr/bin/perl
# converted to perl from the
# C-program for calculating fret distances for any scale length
# Written by Chris St. Pierre
# http://www.buildyourguitar.com/resources/tips/fretdist.htm
use strict;
my ($distance, $scale, $location, $scaling_factor, $num_frets);
$scaling_factor = 0;
$distance = 0;
if ($#ARGV > -1) {
$scale = $ARGV[0];
$num_frets = $ARGV[1] ? $ARGV[1] : 24;
} else {
printf ("Enter the scale desired: ");
$scale = <STDIN>;
printf ("\nEnter the number of frets: ");
$num_frets = <STDIN>;
}
printf("\nFret | Dist bet. frets | Dist to Nut\n");
printf("------------------------------------\n");
my $magic = 2**(1/12);
$magic /= ($magic - 1);
foreach my $current_fret (1 .. $num_frets) {
$location = $scale - $distance;
$scaling_factor = $location / $magic;
$distance += $scaling_factor;
printf("%4d: %10.3f %15.3f\n", $current_fret, $scaling_factor, $distance);
}
printf("=================================\n");
I hope I copy-n-pasted that correctly .
There's also an excel spreadsheet around on that page where I got that C-program:
http://www.buildyourguitar.com/resources/tips/fretdist.htm