CPM Graphing Calculator
Create a Critical Path Method (CPM) network diagram from tasks and dependencies. Instantly calculate ES/EF/LS/LF/Slack, highlight critical tasks, and export a shareable summary.
Enter tasks, durations, and dependencies to calculate CPM schedule fields and render an AON network graph.
| Task ID | Task name | Duration | Dependencies | |
|---|---|---|---|---|
Separate dependencies with commas or spaces (e.g., "B,C" or "B C").
Schedule fields (ES/EF/LS/LF/Slack), total duration, and critical tasks.
Total duration
9
Critical path
A → B → D
Critical tasks (Slack = 0)
| ID | Name | Duration | Predecessors | ES | EF | LS | LF | Slack |
|---|---|---|---|---|---|---|---|---|
| ACritical | Task A | 2 | N/A | 0 | 2 | 0 | 2 | 0 |
| BCritical | Task B | 3 | A | 2 | 5 | 2 | 5 | 0 |
| C | Task C | 1 | A | 2 | 3 | 4 | 5 | 2 |
| DCritical | Task D | 4 | B, C | 5 | 9 | 5 | 9 | 0 |
Slack = LS - ES. Critical tasks have Slack = 0.
A simple activity-on-node graph with critical tasks highlighted.
Get a practical explanation, risks, and next-step recommendations based on your CPM result.
Why this tool is different
Graph + schedule table
AON network diagram plus ES/EF/LS/LF/Slack in one place.
Strong validation
Detect unknown dependencies and cycles before calculating.
Copyable output
Copy a clean summary for homework, reports, or stakeholder updates.
AI insights (optional)
Get practical explanations, risks, and next-step recommendations.
How it works
Add tasks
Enter task IDs, durations, and predecessor IDs.
Get CPM results
We compute ES/EF/LS/LF/Slack and identify critical tasks.
Export and share
Download the graph or copy a summary for reuse.
FAQ
CPM here means Critical Path Method (project management), not advertising CPM. Results depend entirely on the task durations and dependencies you provide.