Gantt Chart Maker

About the Gantt Chart Maker

A Gantt chart shows a project as bars on a calendar: one row a task, each bar from the day the task starts to the day it finishes. Type the tasks, how many working days each takes, and what each must wait for — the chart schedules them for you, skipping weekends and holidays, and draws the links between them.

The critical path is the chain of tasks with no room to slip: if one of them takes a day longer, the whole project finishes a day later. The maker finds it the way project planners have since the 1950s — a forward pass for the earliest dates and a backward pass for the latest — and shows each task's slack, the working days it can slip without delaying the end.

Group tasks into phases by indenting them, mark milestones, record who owns each task and how much is done, and keep a baseline to see how far the plan has moved. Start from an example — a website launch, a product launch, an office move or a conference — or import a task list from a spreadsheet. Up to twenty projects stay in this browser. The chart and the schedule download as PDF (A4 to A2 poster), PNG, SVG or CSV with a Pro pass, which also saves baselines; without one, the finish date shows in full with the first rows of the schedule and a marked chart.

Links, lags and leads

• Finish-to-start: a task starts the working day after the tasks in its After column finish — the usual link, and the one this maker schedules.
• Lag: 3+2 waits two more working days after task 3 finishes, for curing, delivery or approval.
• Lead: 3-1 starts one working day earlier than 3 would — on the last day of task 3 — so the two overlap; 3-2 starts on its last but one.
• Phases: a link to a phase waits for every task in it; a link of a phase holds back every task in it.
• A start you type is kept as “not before”: the task starts on that day or later, if its links need it.
• Links that go round in a circle cannot be scheduled: the maker says which rows they are and leaves one link out until you fix it.

The critical path and slack

The critical path method of Kelley and Walker works out two sets of dates. The forward pass gives each task its earliest start and finish from its links; the latest finish of the project is the end of the longest chain. The backward pass then gives each task the latest dates that still keep that finish. A task's slack (total float) is the difference: zero slack means the task is critical. To finish earlier, shorten a critical task — shortening any other one changes nothing.

Working days and calendars

• Durations are in working days: a 5-day task that starts on a Thursday finishes on the Wednesday after, over the weekend.
• The working week follows your country (Monday to Friday in most of the world, Sunday to Thursday in much of the Middle East, Monday to Saturday where Sunday is the only day off); change it for the project.
• Holidays and days off are skipped like the weekend. Choose Every day to count calendar days.
• A start or finish typed on a day off moves to the next (or, for a finish, the previous) working day, and the page says so.

Files and imports

• PDF: vector pages on A4, A3, A2 (a poster), US Letter or Tabloid, landscape, scaled to the page width at the zoom that fits; long projects continue on further pages with the timeline repeated.
• PNG for slides and chat, SVG for design tools and documents.
• CSV: one row a task with its dates, duration, links, owner, progress, slack and baseline, for a spreadsheet.
• Import a CSV task list from a spreadsheet or another planner: task names, start, finish or duration, predecessors by row number, owner, progress, and WBS numbers (1.2.3) or outline levels for phases. The CSV template shows the columns.
• Backup: the project as a small file you can open again here, in any browser.

Limitations

• Links are finish-to-start; start-to-start, finish-to-finish and start-to-finish links are not scheduled.
• Durations are whole working days; there are no hours, part days or resource levelling, and one calendar applies to the whole project.
• Up to 400 tasks in a project and 20 projects in this browser; save a backup to move a project to another device.
• The PDF draws Latin, Cyrillic, Greek and Vietnamese letters; task names in other scripts (Hindi or Japanese, for example) show as “?” in it, and the page says so — the PNG, SVG and CSV files keep them.

Privacy

Everything happens in your browser. Your projects are kept in this browser’s storage on this device and are never uploaded; imports are read on your device and backup files are made there.