Floats provide information on the slack time available for individual activities. You can use the floats calculated during scheduling in capacity leveling for example, to shift activities between the earliest and latest dates or to extend the duration.

The following floats are calculated in scheduling:

The total float is the time interval in which an activity, starting from its earliest dates can be shifted out into the future without the latest dates of its successors or the basic finish date of the network being affected.

The total float can be smaller than, greater than or equal to zero (total float = latest finish - earliest finish). If the earliest and latest dates of an activity fall on the same day, the total float is zero.

Activities with the smallest total float are called "critical".

The critical path is the path through the network in which the activities and their relationships are ordered so that the total float is minimum. The critical path is in general the longest way to carry out the network.

The free float is the time interval in which an activity, starting from the earliest dates, can be shifted out into the future without the earliest dates of its successors or the basic finish date of the network being affected.

The free float cannot be smaller than zero or larger than the total float. The system first calculates the earliest start date for all successors of the activity and subtracts the offset of the relationship. The smallest of these dates subtracting the earliest start date of an activity, determines the free float.