The four jobs of a project plan
A project plan is asked four questions, over and over, for the whole life of the project. When does it finish? Who is doing what? How much will it cost? Are we on track?
A plan that answers one of them well and the other three by hand is not a plan. It is a picture of a plan. This is the difference between a Gantt chart drawn in a spreadsheet and a scheduling tool, and it is worth being concrete about what the second one has to do.
01 — Plan the time
When will this actually be done?
The finish date is not something you choose. It falls out of the dependencies and durations you entered, and the Critical Path Method is the arithmetic that produces it. Change one duration and every downstream date moves — instantly, not after someone redraws the bars.
What that requires underneath: four dependency types, eight constraint types, split and recurring tasks, nine work-contour types, custom calendars, work weeks, elapsed durations. Unglamorous machinery, but this is exactly the machinery that separates a schedule that survives contact with reality from one that gets abandoned in week three.
02 — Plan the resources
Who is overbooked? Who is idle?
Every task consumes somebody. A plan that does not model that will cheerfully tell you three people can each do two full-time tasks in the same week.
Assign work, material, cost, budget and generic resources to tasks. Resource Usage and Team Planner views surface overallocation the moment it appears rather than the week the deadline slips. Automatic levelling resolves conflicts by priority, slack or ID — and only within available slack if that is what you tell it to do. Rate tables A–E carry date-effective rates and time-varying availability, because people do not cost the same all year and are not available all year.
03 — Plan the cost
How much will it actually cost?
You can price the parts. Pricing the plan is harder, because labour, overtime, materials and vendor fees are all attached to a schedule that keeps moving.
So cost has to roll up from resource rates, fixed costs and material consumption, with fixed-cost accrual at start, end or prorated — and it has to recalculate in the same beat as the schedule. Thirteen Earned Value columns (BCWS, BCWP, CPI, SPI, EAC, VAC, TCPI and the rest) turn that into the two numbers an executive actually reads: are we ahead or behind, and are we over or under.
04 — Track the progress
Are we on track?
"On track" is only meaningful against something. That something is a baseline — the plan as it was promised, kept alongside the plan as it is now.
Eleven baselines (0–10) plus ten interim plans mean you can keep the history rather than overwrite it every time the plan is re-approved. Fifty-five baseline columns and five variance columns give you the comparison; baseline bars overlay the Gantt so you can see it without reading a table. Update Project and Reschedule Uncompleted Work move everything that did not happen past the status date, in one action rather than two hundred.
The part that ties them together
These four jobs are not four tools. The reason they belong in one file is that each answer changes the other three: a slipped task moves the finish date, which moves who is busy in November, which moves the cost, which moves the variance you report.
Ingantt does all four in the browser, at the depth Microsoft Project does them — plus AI to draft and edit the plan, Google Drive to share it, and MS Project and Primavera files in and out. There is no separate AI subscription and no new account to create.
If you are coming from MS Project or Primavera with files in hand, start by opening one and see whether the four answers come back intact.