Ganttly Project Timeline

Ganttly Project Timeline builds a project schedule and Gantt chart from a task list using the critical path method (CPM). It is used by project managers, team leads, consultants, and students planning a thesis.

List tasks with durations, dependencies, and a start date. Ganttly returns early start, early finish, late start, late finish, and total float for each task, the critical path, milestones, and the project end date.

Calendars: plan on business days that skip weekends and the public holidays of a chosen country (with regional holidays, local weekends such as Friday-Saturday, and your own days off such as a year-end shutdown), or on plain calendar days. Durations can be given in days or weeks. Dependencies are finish-to-start and can carry a lag ("Design+2") or a lead ("Build-3"). Tasks can have a start-no-earlier-than date, an owner, or be zero-length milestones.

The interactive chart has a day and week axis, task bars, dependency arrows, the critical path in red, float after each bar, milestone diamonds, and a today line. Tap a task for its dates and float, and test a slip to see the new end date and critical path.

What-if analysis compares up to four scenarios against the plan, for example how far a 5-day slip moves the finish and which tasks become critical.

Downloads: a CSV schedule, an .ics calendar file with milestones and task start dates, and an SVG image of the chart for slides and documents.

The schedule is computed by deterministic code, so the same inputs give the same dates. Dependency loops and unknown task names are explained in plain language.

Example: "Make a Gantt chart starting 2026-11-02: Design 5 days; Build 10 days after Design; Test 4 days after Build; Docs 3 days after Design; Launch milestone after Test and Docs."

Limitations: finish-to-start links only (no start-to-start or finish-to-finish), whole-day scheduling, and no resource levelling, costs, or progress tracking. Plans are not saved or synced with project tools.