Gantt Chart Maker

How to use the gantt chart maker

1. Give each task a name, a start date (year-month-day or the date picker) and a number of days. Add the percent done if you track progress. Use Add a task for up to 40 tasks.
2. To make a task wait for others, type their task numbers in Waits for, for example 1 or 2 3. That task then starts the day after the last of those tasks ends, and its own start date is ignored.
3. The chart, the total length of the plan and the computed dates update as you type. Shade weekends if you want them marked. If a row has a problem, such as a loop of tasks waiting for each other, the message names the row.
4. Use Download PNG or Download SVG for the picture, Download CSV for a table with every task's start and end date, or Copy schedule for plain text.

A four-task plan

How the dates are worked out

A task with no entry in Waits for uses the start date you typed. A task that waits for others looks at when each of them ends, takes the latest end date, and starts the next day. Length counts the first day, so 5 days starting on March 2 ends on March 6. All of this uses calendar days, counted whole, so a daylight saving change never moves a bar.

Tasks may be listed in any order and may wait for a task further down the list. A task that waits for itself, for a task that does not exist, or in a circle of tasks that wait for each other is reported with its row instead of drawing a chart that could not be true.

Reading the chart

Each task is a bar on a calendar with month names and day numbers across the top. The darker part of a bar shows how much is done, and the percentage is printed inside bars wide enough to hold it. Dashed lines join the end of a task to the start of each task that waits for it. Hover over a bar to see its exact dates and length.

Short plans use wide days so every date is labeled. Longer plans use narrower days, down to 2 pixels a day for plans over about 400 days. For the people involved, the org chart maker shows who reports to whom, and for the work itself a Kanban board is easier to update day to day.

What it leaves out

This planner schedules calendar days only. It does not skip weekends or holidays, balance workloads, or move tasks automatically when a date changes. If you work only on weekdays, count weekdays with the business days calculator and enter the result as the number of days.

Assumptions and limits

• Dependencies are finish to start: a task begins the day after the tasks it waits for end. Overlaps, delays and lead times are not modeled.
• Days are calendar days. A task of 5 days starting on a Friday ends on the next Tuesday.
• Dates must be between 1900 and 2200, a task can be up to 3,650 days long, and a whole plan can span up to 5,000 days.
• Task numbers in Waits for refer to the numbers shown on each task card, so removing a task renumbers the ones below it. Check those entries after removing a task.

Formulas reviewed October 10, 2026. See the calculation methodology for how SumPanda rounds, tests and sources its formulas.

Frequently asked questions