For most music notation software, due to the complex nature of modern staff notation, extra mouse interactions and manual efforts are highly demanded. According to this observation, we propose MusicTXT, a plain textbased user interface for music notation that is almost mouse interaction-free. Based on our easy-to-learn online user interface, users are able to notate music by typing a paragraph of numbers and alphabets as plain text. We validated the music notation efficiency of our interface by comparing it with another popular online software-NoteFlight. According to statistical analysis, we prove there is a significant improvement in music notation efficiency by using MusicTXT.