Total Float
Scheduling Terms
Reviewed by forProject Technology - updated Sep 2026
Quick definition: Total Float (also called Total Slack) is the amount of time a task can be delayed from its Early Start without delaying the project finish date or any other date the schedule is required to meet.
Total Float is calculated as the smaller of Late Finish minus Early Finish, or Late Start minus Early Start. It can be positive, meaning the task has spare time, or negative (Negative Float), meaning the schedule doesn't allow enough time to meet a required date. Microsoft Project calls it Total Slack; Primavera P6 and some other scheduling tools call it Total Float.
What this means for you
Total Float shows how much scheduling cushion each task has, which determines whether that task sits on the Critical Path. Negative Float is a red flag: it means a required date is at risk unless something in the schedule changes.
Also known as
Total Slack
Used in
Critical Path; Critical Path Method
See also
FAQ
What does negative Total Float mean?
It means there isn't enough time scheduled to meet a required date, either on that task or somewhere downstream. Time needs to be saved or recovered somewhere in the schedule.
How does Total Float relate to the Critical Path?
Tasks with the least Total Float in the schedule, often zero, make up the Critical Path.
Definition maintained by forProject Technology.
© 2026 forProject Technology, Inc.
© 2026 forProject Technology, Inc.
