LogonTracer is a tool designed to investigate malicious logons by visualizing and analyzing Windows Active Directory event logs. It associates host names or IP addresses with account names found in logon-related events, displaying them as a graph to identify the account where login attempts occur and the host used. LogonTracer can visualize event IDs related to Windows logon, such as 4624 for successful logon, 4625 for logon failure, 4768 for Kerberos Authentication (TGT Request), 4769 for Kerberos Service Ticket (ST Request), 4776 for NTLM Authentication, and 4672 for assigning special privileges. The tool utilizes PageRank, Hidden Markov model, and ChangeFinder for detecting malicious hosts and accounts from event logs, and can display event logs chronologically. LogonTracer can be used by installing it via docker and referring to its documentation for further details.