To reset your password in Piwik, go to Piwik: below the login screen you will find a link “Lost your password?”. After clicking the link, enter your Piwik username or Email address, and a link to reset your password will be sent to your email address.
Note: for security reasons, it is not possible to recover passwords, but only change them. We highly recommend to use a strong password and to enable automatic SSL for login screen in your Piwik server.