Schedule analysis tool

Critical Path Calculator

Move activity durations and see the critical route, project duration, and total float update.

Opening-night schedule lab

Move the durations. Watch the critical path change.

Try a preset or change an activity’s duration.

Activity durations

All relationships are finish-to-start. Day 0 is the start of setup.

A. Raise the entrance arch2 days

Can start immediately

B. Hang the midway lights4 days

After A

C. Tune the carousel organ3 days

After A

D. Inspect the Ferris wheel5 days

After A

E. Test the night circuit3 days

After B

F. Rehearse the opening parade2 days

After C

G. Complete the final safety walk2 days

After D, E, F

Live opening plan

Critical route

Midway lights

ABEG

Carousel parade

ACFG

Ferris wheel

ADG

Critical path schedule calculations for each activity
Activity	ES	EF	LS	LF	Float
A
B
C
D
E
F
G

Reading the table: ES/EF are the earliest start and finish. LS/LF are the latest start and finish that preserve the current opening date. Total float is LS − ES.

For the worked example and reasoning, read the related study guide.

How it works

Change an activity duration and the calculator runs the forward and backward passes again. It identifies the longest route, project duration, and total float for every activity.

Example to try

Start with the opening plan, then choose Two routes tie. Both routes finish in 11 days, showing why shortening only one critical route may not move the finish date.

Read the result

Activities with zero total float are critical in the current schedule. The critical path can change when durations change, and tied longest routes are all critical.