Gantt Generator
Free Gantt Generator: list tasks with a start day and a duration, then build a stacked bar chart and hide the “start” series — or use the live generator...
Want a drag-and-drop Gantt in your sheet?
The auto-scaling Gantt ships inside the Project Manager's Toolkit — formula-driven, unlocked, ready to print.
How it works
In Excel or Google Sheets, list tasks with a start day and a duration, then build a stacked bar chart and hide the “start” series — or use the live generator above.
List each task with a start day (or date) and a duration in days.
Insert a Stacked Bar chart from the start and duration columns.
Select the “start” series and set its fill to No Fill so only the duration bars show.
Reverse the category axis so the first task sits at the top.
What this does
A Gantt chart turns a task list into horizontal bars on a timeline, so you can see at a glance what runs when and what overlaps. The classic spreadsheet trick is a stacked bar chart: one invisible series offsets each bar to its start day, and a second visible series draws the duration. Each task needs just a name, a start and a length.
A worked example
Four tasks — Research (start 0, 4 days), Design (3, 5), Build (7, 8), Launch (14, 2) — lay out on a 16-day timeline. Research and Design overlap by one day; Build starts as Design finishes. The generator above scales every bar to the longest timeline automatically, so adding a task or stretching a duration redraws the whole chart instantly. A Gantt chart is how a plan becomes a picture everyone can read — stakeholders see the schedule, the team sees the overlaps, and you see the critical path. Building it from a simple table keeps it editable as the plan changes.
Common mistakes
- Plotting end dates instead of durations, which a stacked bar cannot offset correctly.
- Forgetting to hide the offset series, so every bar starts at day zero.
- Leaving the task order reversed (Excel plots bottom-up by default).
- Hard-coding bar positions instead of driving them from start/duration cells you can edit.
FAQ
Do I need project software for a Gantt?
No — a stacked bar chart, or the generator on this page, produces a clean Gantt from a simple task/start/duration table.
How do I show dependencies?
Set each task’s start to the previous task’s end (=prev_start+prev_duration). The bars then cascade, and changing one shifts the rest.
Can I use real dates?
Yes — use date cells for the start and a duration in days; the same stacked-bar method works with the date axis.
Built in your browser when you click. Nothing is uploaded, no signup, free for commercial use.