This site is no longer being maintained and I've decided to revive this project. Please visit http://www.testav.com!
This is ONLY A TEST FILE. But please use it at your own risk.
This is a 70-byte file which, if executed, simply displays the message:
This is a 186-byte WinZip file containing one file (eicar.com above), which will test whether your anti-virus software detects the test virus in a zipped file.
This is a 252-byte WinZip file containing one file (eicar.zip above), which will test whether your anti-virus software detects the test virus in a double-zipped file.
Remember, the EICAR test virus is not really a virus. It cannot do any harm to your system, even if your software does not detect it. But still use it at your own risk.
Source: Rex Swain's website