Compare two Primavera P6 schedule updates
Contractors send monthly schedule updates as XER files, the export format of Oracle Primavera P6. Reviewing them usually needs a P6 licence and an afternoon of side-by-side scrolling. Upload the earlier and the later update here and you get one report of everything that changed: how far the finish moved, which activities slipped, what was added or deleted, logic and duration edits, float erosion, calendar edits, progress against the plan, resource and cost changes, and recorded history that was rewritten.
Upload a single XER instead and you get a schedule health check in the style of the DCMA 14-point assessment.
What to upload
| You have | Upload |
|---|---|
| Two updates of the same project | the earlier one first, the later one second (.xer, or each in a .zip) |
| Both updates in one ZIP | the ZIP as the earlier update; the two files are put in order by data date |
| One schedule | only the first file, for the health check |
In P6 the export is File, Export, Primavera PM (XER). A P6 XML export, a Microsoft Project file, a PDF or a spreadsheet can't be compared.
What the comparison shows
- Headline: data date and forecast finish of both updates, the finish movement, counts of added, deleted, started and finished activities, logic edits and new negative float, and the float on the finishing activity.
- Findings: a short list of what deserves a closer look, from a finish slip or changed actual dates to edited calendars and original durations.
- Activities that slipped most, milestones and every start and finish change.
- Added and deleted activities, with a note when deleted work had already started.
- Duration changes: original durations, remaining durations changed before the work began and remaining durations that grew.
- Progress this period, and the starts and finishes the earlier update planned for the period that did not happen.
- Changed actual dates: recorded actual starts and finishes that moved or disappeared.
- Relationship changes: added, deleted, type and lag changes, with the ones caused only by an added or deleted activity marked as such.
- Constraint changes, calendar changes and calendar assignment changes.
- Total float changes, critical and longest path changes and out-of-sequence progress.
- Resources and costs of resource-loaded schedules: budgeted, actual and at-completion units and costs by labor, nonlabor and material and for expenses, the budget of each resource in both updates, and every resource assignment or expense that was added, removed or re-budgeted, had its price changed, or whose remaining units grew. Actual units or costs that went down are flagged.
- Name, type, WBS, duration type and percent-complete type changes, the project and scheduling settings side by side, and the health checks of both updates.
How the numbers are worked out
- Activities are matched by Activity ID. P6 gives every copied project new internal ids, so those are only used to recognise an edited Activity ID when both files are exports of the same P6 project.
- Relationships are matched by predecessor, successor and type. P6 allows an SS and an FF between the same two activities, so both are kept apart.
- Calendars are matched by name, and their work week, hours per day and holiday or exception dates are compared, including holidays inherited from a base calendar. A project copy that renumbers its calendars shows no change; a holiday added to a calendar does.
- Dates, total float and the longest-path flag are the values P6 stored in each file. Nothing is rescheduled. Date movements are calendar days; durations, lags and float are working days of each activity's calendar.
- Resource assignments are matched by activity and resource ID (role ID for role assignments), expenses by activity and expense item. Units are hours (material: its own unit) and costs are in the database's base currency, as stored in the files.
Health check of one schedule
The checks follow the DCMA 14-point assessment: missing logic, leads, lags, relationship types, hard constraints, high float, negative float, high duration, invalid dates, resources, missed tasks, critical path continuity, CPLI and BEI. Every finding lists the activities behind it, next to the critical path, out-of-sequence progress, the float distribution and the calendars in use.
What you get
- An HTML report with every section, which opens in any browser and prints.
- An Excel workbook with a summary sheet, one sheet per section and every activity side by side, with real dates and numbers so the sheets sort and filter.
- A CSV change list: one row per change (or per finding in a health check).
The summary, the findings and the slipped activities are shown on this page.
Good to know
- Tested with real exports from P6 5.0, 8.2, 17.12 and 23.12, including a baseline with four monthly updates of one project, files of over 5,000 activities and files written in Windows code pages (Western and Arabic) or UTF-8.
- An XER with several projects works: the projects whose Activity IDs match each other are used, and the report says which. Enter a Project ID under More options to choose another.
- Recalculate (F9) in P6 before exporting: a file edited after the last schedule run carries stale dates and float, and so does the report.
- Your uploads are deleted as soon as the comparison finishes and the reports are deleted after 30 minutes. Activity names and project details never go into our statistics.