Dupli Checker- FREE
Grammarly- "Grammarly is an automated proofreader and plagiarism checker. It corrects up to 10 times as many mistakes as other word processors". $$
Noplag- FREE
Paper Rater- free and $$ accounts
The Plagiarism Checker- free and $$ accounts
Plagiarism Checker.com- FREE
Plagiarism Detector- paste the file or upload; FREE
PlagiarismSearch.com- free check
Plagiarisma- FREE
Plagium- free and $$ accounts
Plagscan- FREE; upload or paste
Quetext- only copy and paste; no uploading of files
Unplag- paste text or upload your file
Viper Plagiarism Scanner- Windows only; requires download
