Program that finds duplicate words in a text?

[Dimitri]

Is there a program, or preferably, an online thing where I could just copy paste a text, that can detect duplicate words in the text?

It would be great if I can also tell it to ignore duplicates of certain words, but that's not essential.

 

[Cromewell]

http://www.writewords.org.uk/word_count.asp works. It shows the number of times a word appears for every word in the text. Not sure if that's exactly what you're looking for but I suspect it's probably close enough.

 

[Agent Smith]

I believe DocPad will do this as well. If you're looking to find words in a whole bunch of text, check out Fileseek and if you want to compare two text docs or anything with text like a HTML or PHP doc check out Winmerge.