Guide lines is a free Chrome add-on developed by imagentleman (José Antonio Chio) that allows users to easily check the visual alignment of page elements. With this add-on, users can get a vertical guide and a horizontal guide that follow their mouse and go across the entire viewport. This tool is particularly useful for web developers and designers who need to quickly check the alignment of elements on a page.

Guide lines features a simple and intuitive interface, making it easy to use for both beginners and experienced users. The add-on also provides a visual guide that helps users identify any alignment issues and make necessary adjustments. By using Guide lines, users can ensure that their webpages are visually appealing and properly aligned.

Overall, Guide lines is a valuable tool for web developers and designers who want to ensure the visual alignment of their page elements. With its easy-to-use interface and helpful features, this Chrome add-on is a must-have for anyone working on web design projects.