This article provides you with the background information on the Gantt chart view for Trello and Planner. If you are looking for specific features or advanced guides, please check the Gantt help center section.
View Trello or Planner board as Gantt chart
This GIF will show you how to import your board from Trello into Placker and gives you a short introduction on the Gantt chart. Basically, after you have imported a Trello or Planner board to Placker, you can open it at Placker.com or using one of the power-up buttons and access the Gantt view.
For more details on this view mode, check the Gantt help center section.