Estimate Activity Durations Process: PMP Exam Guide

estimate activity resources
According to the PMP process map, after defining what the project activities are, immediately after sequencing the activities and estimating the activity resources, the process of estimating the activity duration comes next. Estimate activity duration process is simply about estimating activity durations by using estimation tools and techniques, taking the factors such as people doing the job, when the resources will be available, what are the characteristics of the resources, the size of the work to be done. In the PMP exam, you may come across questions asking when to conduct estimate activity durations process, which inputs and tools and techniques are used while conducting this process.


A working period is the time measured when doing a job. This unit of time can be days, months, years, hours depending on the size of the activity. In estimate activity durations process, working periods are used to estimate the duration of activities. This estimation process will be highly dependent on attributes of activities, characteristics and capabilities of resources used and availability of resources. Therefore we will need some inputs in order to be able to estimate activity durations.

Estimate activity durations process is performed as a part planning process group and schedule management knowledge area.

Outputs Created in Estimate Activity Durations Process

  • Activity duration estimates
  • Basis of estimates

Outputs Updated in Estimate Activity Durations Process

  • Activity attributes
  • Assumption log
  • Lessons learned register

Inputs used while Estimating Activity Durations

  • Activity list
  • Activity attributes
  • Schedule management plan
  • Scope baseline
  • Assumption log
  • Lessons learned register
  • Milestone list
  • Project team assignments
  • Resource breakdown structure
  • Resource calendars
  • Resource requirements
  • Risk register
  • Enterprise environmental factors
  • Organizational process assets

Tools & Techniques used in Estimation of Activity Durations

  • Analogous estimating
  • Parametric estimating
  • Bottom-up estimating
  • Three-point estimating
  • Alternatives analysis
  • Reserve analysis
  • Voting
  • Meetings
  • Expert judgment