LogicReader calculates the critical path with the same logic as Primavera P6 — the longest chain of activities through the schedule, where any delay shifts the project finish date. We add one thing on top: the path is rendered as a continuous, readable chain, not a stripe of red bars at random places on a Gantt.
Running the calculation
- Load the schedule.
- Click Critical Path in the toolbar.
- The longest chain highlights in red. Activities not on the critical path drop to a low-contrast grey.
The calculation runs in the browser and is fast enough to feel instant up to a few thousand activities. On schedules above ~25,000 activities you may see a one- or two-second pause the first time you run it; subsequent runs are cached.
N-th longest path
Critical Path can also surface the second-longest, third-longest and so on — the chains a planner usually calls “near-critical.” Click the small ↑ / ↓ arrows next to the Critical Path button to step through them. Each chain renders in a different shade so you can see them stacked.
This is the early version of what will become a Cypher-driven longest-path query when the Neo4j integration lands fully — for now it runs against the in-memory graph.
Combining with Isolate
Critical Path + Isolate is the most common workflow:
- Click Critical Path.
- Click Isolate.
- You now have a one-screen diagram of just the critical chain — ideal for a steering meeting.
What “critical path” does NOT mean here
LogicReader’s critical path is the calculated CPM critical path — longest chain to project finish. It is not:
- The most important chain commercially. The two often differ.
- A risk-adjusted critical path. There’s no Monte Carlo here.
- The Critical Chain in CCPM. CCPM is on the roadmap as a separate calculation mode.
Senior planners tend to want all four readings of “critical.” Today LogicReader gives you the first one cleanly. The others are scoped on the roadmap.