log_sense is a log analysis tool which analyzes Ruby on Rails and Apache/Nginx logs and provides detailed data about accesses, performances, and errors. It is a one-stop shop solution for analyzing your Rails application in production. Simple to use and working from the command line, it does not require any modification to your app (e.g., no need to change the log format, no cookies, no JavaScript code, no infrastructure to setup). We use it to monitor our applications in production, using a cron job which pulls the logs and calls log_sense to generate HTML reports. Compatible with Ruby on Rails default logs up to version 8.0.2 and with the combined Apache/Nginx format.