The best alternatives to GANTTplanner are Sergei Vaskov, Gantt, and Quire. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of GANTTplanner?
AssemblyAI— Speech-to-Text API with superhuman accuracy
Gantt.io creates amazing Gantt charts for you in no time. Beautiful templates, a very intuitive and efficient interface, multi-user editing, time-travel as well as a high-res export function allow you to create THE chart that will convince your audience.
Quire is a collaborative project management tool that allows users to easily plan and organize tasks easily in a tree-like structure, where goals are achieved by breaking ideas down into doable tasks that are nested in a hierarchical list.
A free MS Project alternative for simple gantt charts. Create project plans with tasks and schedules. Save asgantt files and share with anyone to open and edit for free with a web browser. No need to buy any license or install any software.