If you want to check against the Internet - Copyscape If you want to check a spun article for uniqueness, Dupecop Or just enclose the text string in quotes and try Google
I noticed that sometimes CopyScape doesn`t find duplicate content. I used to check an article and find nothing with CS and on second check it found me duplicate content. It happened to me a few times. I wonder why?
Your anwser is very useful to me. The result of CopyScape is not right usually. I will try Dupecop. Thank you very much.
I agree with the recommendation of Copyscape Its fairly inexpensive and can save you a fair amount of wasted time - and as well reassure that everything is on the up and up