The critical path consists of the longest sequence of activities from project start to finish that must be completed to ensure the project is finished by a certain time.
Critical path gives a higher level of insight into your project’s timeline thus, giving you more understanding about which task duration you can modify, and which must stay the same.
Formula to calculate critical path.
Add all the time leading to the last event using different paths given and the sequence that takes the longest time is the critical path.
Example:
| Path | Time |
| 1-2 | 3 days |
| 1-3 | 4 days |
| 1-4 | 7 days |
| 4-5 | 5 days |
| 5-6 | 2 days |
| 2-6 | 1 day |
| 3-6 | 2 days |
Drawing a diagram to represent the critical path is an easy way to determine the paths.
To get the critical path we add up the days taken via every path to 6.
1-2, 2-6, = 3 + 1
= 4 days
1-3, 3-6, = 4 + 2
= 6 days.
1-4, 4-5, 5-6 = 7 + 5 + 2
= 14 days
Therefore, since the critical path is the path with the longest sequence, here, our critical path will be 1-4, 4-5, 5-6.
