Gantt planning¶

The Gantt view places the tasks of your projects on a timeline, so that you can plan them, shift them, and see at a glance where the schedule breaks.

Note

This feature is provided by the Project Gantt (project_gantt) module.

Planned dates¶

The Gantt bar of a task is drawn between its Start Date and its Planned End; both fields are on the task form, next to the Deadline. The deadline itself is kept separate and is drawn on the chart as a marker, so that the plan and the commitment stay distinguishable.

Two more fields control how the task appears:

Progress – the completion percentage drawn inside the bar.
Gantt Shape – Task draws a bar, Milestone draws a diamond.

Two buttons are available on tasks that are scheduled:

Unschedule clears the planned dates and moves the task back to the unscheduled list.
Save Baseline stores the current planned dates as the baseline, which is then drawn under the bar so later changes to the plan remain visible.

Important

The planned end date must not be earlier than the planned start date, and the progress must be between 0 and 100.

Working in the Gantt view¶

Open Project ‣ Tasks (or the tasks of a project) and switch to the Gantt view. The view opens on the Month scale, grouped by assignee, and offers the Day, Week, Month, and Year scales.

In this view you can:

drag a bar to move a task, or drag its edge to change its duration; dates snap to the scale, and non-working days are skipped;
draw a bar in an empty cell to plan an unscheduled task;
open the Unscheduled panel to plan the tasks that have no dates yet;
shift the successors of a task automatically when you move it;
display the columns Assignees, Stage, Allocated Hours, and Deadline next to the chart;
show the critical path, the baseline, and the workload of the assignees.

Tasks are colored by project, and tasks that overlap or whose dependencies are inconsistent are highlighted in red.

screenshot: services-project-gantt-view

menu: Project ‣ Tasks ‣ (Gantt view)
shows: The Gantt view of project tasks on the Month scale, grouped by assignee, with several bars, one milestone diamond, a dependency arrow between two tasks, and one bar highlighted in red.
highlight: The scale selector and the red (conflicting) bar (red frames).
data: Project "Boiler maintenance 2026" with about eight tasks across two assignees.
module: project_gantt
notes: English UI, light theme, 1440px width, crop to the chart area.

Dependencies between tasks¶

Dependencies can be drawn directly in the chart, or maintained in the Gantt Links tab of the task, which lists the incoming and the outgoing links. Each link has:

a Type: Finish to Start, Start to Start, Finish to Finish, or Start to Finish;
a Lag (days), a positive delay or a negative lead between the two tasks.

Note

A task cannot be linked to itself, the same pair cannot be linked twice, and circular chains of dependencies are refused.
Finish to Start links are kept in sync with the standard task dependencies of the task, so both views of the same relationship stay consistent.

When a predecessor finishes later than its successor should start, taking the lag into account, the successor is flagged and drawn in red until the plan is corrected.