Project scheduling software that reschedules when reality does
Onplana project management is project scheduling software with a real scheduling engine: the critical path recomputed on every change, all four dependency types with lead and lag, all eight Microsoft Project constraint types, baselines with the variance worked out, working calendars, resource leveling, and import from .mpp and Primavera .xer, on every plan, including Free.
Updated . The Microsoft prices on this page were read on microsoft.com that day.
What changes when the schedule moves on its own?
A spreadsheet or a Gantt drawn by hand is a picture of a plan. The engine is what makes it a schedule.
Scheduling by hand
- Re-key the successor dates by hand after a slip, one task at a time, and hope none was missed.
- Re-read the whole chain to work out which tasks are critical this week.
- Keep the agreed plan in a second spreadsheet to answer "how late are we".
- Re-type the lag and the constraints that a Finish-to-Start-only import dropped.
- Level by moving bars around until the week looks plausible.
With a scheduling engine
- Drag one bar and the cascade through every successor shows before you apply it.
- The critical path and each task's float are recomputed on every change and painted on the chart.
- The baseline sits behind every bar, and the variance by task is a report you open.
- The import keeps all four link types, the lag to the minute and all eight constraint types.
- Level resources from the toolbar and choose which proposed moves to apply.
How does scheduling work in Onplana project management?
Step 1
Bring the plan in, or write it down
Upload a .mpp, Project XML, .mpx or Primavera .xer, or an Excel or CSV work breakdown, up to 50 MB. Tasks, dependencies with their type and lag, constraints, resources and costs come across in one pass. Or describe the plan and let the AI draft the tasks, dates and dependencies for you to edit.
Step 2
Link tasks with the type and lag you mean
Finish-to-Start, Start-to-Start, Finish-to-Finish or Start-to-Finish, with lead or lag in days, hours or minutes. Set a constraint and its date, or a deadline, on the task itself. A link that would loop back on itself is refused when you draw it, with the tasks named.
Step 3
Read the critical path and float, then move things
The critical path is recomputed on every change and highlighted across the chart, with a float label on each bar if you want one. Drag a bar and the cascade through its successors shows before you apply it. Level resources from the same toolbar and keep the proposed moves you agree with.
Step 4
Save a baseline and read the slip
Capture a baseline at kickoff and before every replan. The Baseline tab reports the variance by task: start, finish, planned duration and actual start against the plan you agreed, the slip in the project finish, and an on-track, at-risk or behind rating.
The engine is the same one the Gantt chart with critical path page describes in Microsoft Project's own vocabulary, and the task dependencies page covers what survives a move off Microsoft Project. The theory behind the forward and backward pass is the blog's critical path method explainer.
Is the critical path computed, or just drawn?
On microsoft.com on October 6, 2026, baselines, the critical path and advanced dependencies with lead and lag are listed among the highlights of Planner and Project Plan 3 at $30.00 per user per month paid yearly, and not among Planner Plan 1's at $10.00; Onplana project management computes all three on every plan, including Free, and its scheduling engine models all eight Microsoft Project constraint types, which is Microsoft's own count.
Neither number is ours to assert: Microsoft's Planner plans page lists the highlights per plan, and its Constraint Type field reference lists the eight types. For your own file, the free Schedule Health Check reads it and reports what it found, dependency counts included, before you create anything.
Which project scheduling software should you choose?
Keep the spreadsheet while nobody depends on anybody else, choose Microsoft Project for one scheduler on Windows, and choose Onplana project management when a team needs the critical path, constraints and baselines on a plan it works together.
| Decision | A spreadsheet | Microsoft Project | Onplana project management |
|---|---|---|---|
| Best for | A list of dated tasks that one person keeps by hand. | One scheduler who builds and owns a plan on a Windows PC. | A team that works one plan together and needs the critical path, constraints and baselines on it. |
| Starting price (read October 6, 2026) | Already paid for on most desks, which is why most plans start there. | $10.00 per user per month for Planner Plan 1; $30.00 per user per month for Planner and Project Plan 3, the plan whose highlights list baselines, the critical path and lead and lag; both paid yearly. Project Standard 2024 is $679.99 one-time. | Free for up to 5 members and 2 projects, then from $7 per seat per month. |
| Critical path | None. A column of dates has no logic behind it. | Computed, on Plan 3 and in the desktop app. Not among Plan 1's listed highlights. | Computed on every change, on every plan, including Free, with the float on each bar. |
| Dependencies and lag | A formula per cell, if somebody writes one. | Finish-to-start on Plan 1; lead and lag on Plan 3 and in the desktop app. | All four types with lead and lag in days, hours or minutes, and all eight constraint types. |
| Baselines and variance | A second tab, compared by eye. | Plan 3 and the desktop app. | As many as you capture, with the variance by task worked out for you. |
| Resource leveling | By moving dates until the week looks plausible. | Listed under Project Standard 2024 and up. | From the Gantt toolbar: it proposes later starts for the over-allocated weeks and you choose which to apply. |
| Opens your existing files | An Excel export of a plan loses the logic that scheduled it. | .mpp is its own format. | Imports .mpp, Project XML, .mpx, Primavera .xer, Excel and CSV; exports Project XML, Excel and a Gantt PDF. |
| When NOT to choose it | When more than a handful of tasks depend on each other, or anyone will ask how late you are against the plan you agreed. | When more than one person has to work the plan at once, or it has to be read from a phone or an AI assistant. | When your schedule depends on sub-day lag (the web app moves in whole working days), on Critical Chain scheduling (not a mode here), or on VBA macros (no equivalent). |
The Microsoft column is what its Planner plans and Project plans pages listed on October 6, 2026. Scheduling a construction programme is its own decision, with a field-operations line we do not cross: construction scheduling software.
What does it cost, and what does it not do?
The Gantt with critical path, all four dependency types, baselines with variance, working calendars and project file import are on every plan, including Free, with no seat minimum; paid plans start at $7 per seat per month. Seeing one person's load across every project is capacity planning, on the Professional plan and up. It replaces the spreadsheet somebody re-dates every Monday, and the desktop licence kept purely so one person can still open the schedule. If that one person would rather stay on their own machine, Onplana Schedule is a free Windows and Mac app that opens, edits and saves the same files.
The honest limit
The web app schedules in whole working days. A lag of four hours or a half-day task is stored exactly, shown exactly and written back out exactly, but it will not shift a successor by part of a day the way Microsoft Project does. Minute-level scheduling lives in the desktop app, Onplana Schedule, which works in working minutes. Leveling also runs on one schedule at a time: it shows a clash across projects rather than resolving it.
Try it on a real schedule
Have a Microsoft Project or Primavera file? Run the free Schedule Health Check and get the audit before you sign up. Only need to look at a P6 .xer first? The free XER viewer opens it in the browser. Have a task list in a spreadsheet? Paste it into the generator and get a Gantt chart with the critical path through it, in your browser, with nothing uploaded. Details of what comes across on an import are on the import and export page; the baseline report is on baselines and variance, and capacity across projects on resource management.
What do people ask before they move a schedule here?
Does the schedule really move when a predecessor slips?
Yes. Move a task and every successor reflows through its link type and lag, honouring the constraints and the project calendar, and the critical path is recomputed. A task that has already started holds its start whatever its predecessors do, and its remaining work is counted from the project status date, which is how Microsoft Project treats actuals too.
Do the links, lag and constraints in my .mpp survive the import?
Yes. All four dependency types come across, each keeping its lag to the minute, and all eight Microsoft Project constraint types come across one to one rather than reduced to four. Working calendars do not: the project uses your organization's working calendar, so set its working days and holidays first.
Can I schedule a Primavera P6 .xer file here?
Yes. A P6 .xer imports with its activities, relationships, lag and constraints, and schedules like any other plan. Two limits to know first: a P6 file carries no baseline, so capture one after the import, and Onplana writes Project XML rather than .xer, so a plan cannot go back to P6 as an .xer file.
Does it level resources, and across projects?
Leveling runs on one schedule at a time: it finds the over-allocated weeks in that plan, proposes later starts for lower-priority tasks and keeps critical, high-priority and constrained tasks in place, and you choose which moves to apply. Seeing one person's load across every project is capacity planning, on the Professional plan and up, and it shows a clash across projects rather than resolving it.
Which plan is the scheduling on?
Every plan, including Free: the Gantt with critical path, all four dependency types, baselines with variance, working calendars and project file import, with no seat minimum. Capacity planning across projects is on the Professional plan and up.
Can I schedule in hours and minutes rather than days?
In the web app, no. It schedules in whole working days, with a day as long as the project calendar says, so a four-hour lag is stored and written back exactly but does not shift a successor by half a day. Onplana Schedule, the free Windows and Mac app, schedules in working minutes and holds a file Microsoft Project scheduled to the minute.
Is it suitable for a construction programme?
The scheduling half, yes: critical path, constraints, baselines, the DCMA 14-point schedule quality check, and import from .mpp and Primavera .xer. It is not field-operations software, so there are no daily logs, RFIs or submittals. The construction scheduling page says exactly where that line is.
Put a schedule under the plan, not a picture
The critical path, four link types with lag, baselines and calendars on the Free plan. Nothing to install, and the file you have stays exactly as it is.
Start scheduling free