See the critical path.
Enter up to twelve activities, tell the calculator what each one waits for, and watch the schedule build itself: bars with predecessor and successor arrows, a network diagram and a float chart, the way you would read them in Primavera P6.
Build your schedule
Give each activity an ID, a name and a duration in days. In Predecessors, list the IDs it waits for. A plain number means finish-to-start. You can also use SS, FF or SF and a lag, as in P6.
| Activity ID | Activity name | Duration (days) | Predecessors | Remove |
|---|
Predecessor examples: 1 finish-to-start · 2SS+5 starts 5 days after activity 2 starts · 3FF-2 finishes 2 days before activity 3 finishes · 1, 4 waits for both. Use a duration of 0 for a milestone.
1 · Bar chart with predecessor and successor arrows
Each bar runs from the early start to the early finish. Arrows run from predecessor to successor. Red bars and arrows are the critical path. Hatched amber shows float: how far the activity can slip without delaying the finish.
2 · Network logic diagram
The same schedule as boxes and arrows. Each box shows early start (ES), duration, early finish (EF), late start (LS), total float and late finish (LF).
3 · Total float by activity
Green bars have comfortable float. Amber bars are near-critical (within 10% of the project duration). Zero float means the activity is on the critical path.
Results table
| ID | Activity | Dur | ES | EF | LS | LF | Total float | Free float | Status | Start date |
|---|
Planning tool. Day numbers count from the start of the project (day 0). Everything is calculated in your browser; nothing is sent or stored. Real projects have calendars, constraints, resources and progress that a scheduling system and a forensic review account for. That is what we do: talk to us about your schedule.