After a lot of confusion on another forum over ratios and display aspect, I decided to write a little (24Kb zipped) Excel 2000 calculator for personal use. Among other things, it calculates aspect ratios and output dimensions instantly from the source dimensions, taking into account cropping, DAR, and Modulus, using sensible rounding techniques.
There are full instructions by clicking on the column headers. Fixed templates include popular HD and DVD formats. There are over 200 user lines available, and the spreadsheet is preformatted for most printers. If I've done my work this afternoon, it should be bulletproof.
If some knowledgeable users want to download, test, debug, and share comments, I will appreciate the feedback. In any event, it's free for noncommercial use. Latest (beta) version will always be here:
[link down for repairs]