<p>Disclosed herein is a computer implemented method and system for enabling a user to anonymously participate in trials over multiple sessions. A temporary user identifier is generated for the user. The temporary user identifier is stored locally on a client device of the user. Anonymous access to multiple online tools on a host website is granted to the user for a predetermined period of time using the temporary user identifier. The user may participate anonymously in the trials over the multiple sessions using the online tools for the predetermined period of time. The participation in the trials comprises performing online activities on the host website by the user. The user may register with the host website by providing user identification information to obtain unlimited access to the online tools.</p>