Free tool
Compare two P6 programmes (XER revision check)
Load the previous and the current update of the same project and see exactly what changed beyond progress: added and deleted activities, changed durations, logic and lags, new constraints, calendar changes, edited actual dates and the movement of the finish date. The files are read in your browser and never leave your computer.
Project
See every change, activity by activity
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Changes found? Show what they did to the critical path.
Chronaxis runs the half-step windows analysis that separates progress from revisions, and writes it up for the claim or the review.
Join the founders listWhy compare updates?
Each programme update should differ from the last only by progress. In practice, durations are shortened, logic is removed, constraints are added and actual dates are rewritten, sometimes to hide delay and sometimes by honest mistake. AACE 29R-03 and the SCL Protocol both expect these revisions to be identified and treated separately from progress, which is exactly what the half-step in a windows analysis does.
This check matches activities by their Activity ID and reports:
- Added and deleted activities, by Activity ID.
- Original duration changes on activities that have not finished.
- Logic changes: relationships added or removed, type changes (FS, SS, FF, SF) and lag changes.
- Constraints added, removed or moved, and calendar changes.
- Edited actual dates: actual starts or finishes that were already recorded in the previous update but are different now.
- Finish date movement and the change in total float on the critical activities.