Effort Vs. Duration Vs. Elapsed Time: Project Management

The estimated duration of a project affects the time it takes to plan and deliver. Poor estimation can result in longer turnaround times and drawn-out delays, which can negatively affect a company's bottom line. It can also raise doubts about a project manager's competence.

The deadline also affects the pricing of a contract, which can impact its profitability. These three factors are used to prioritize scheduled activities during the estimated activity duration - effort, duration, and elapsed time.

What is Effort?

The amount of time it would take to complete a task is referred to as the effort in project management. It can be expressed in days, weeks, or hours.

The goal of the effort is to measure the amount of progress that a project has made. For instance, if you have ten tasks, each of them would take around 30 days to complete. Using the total effort of the various functions of the project, you can easily determine how much progress has already been made.

If you're working on two projects at the same time, each with ten tasks, you can estimate that the total effort involved in each project would be around 20 and 60 days. You can then use the attempt to determine if both projects are running at the exact same speed by estimating that they have completed all the tasks within 60 days.

What is Duration?

The project duration is the amount of time it will take to complete. It can be expressed in terms of days, weeks, or years. The factors that affect a project's duration include the scope of the project, the availability of resources, and the constraints of the client.

One of the most critical concepts in project management is the duration of a project. It shows how long it will take to finish the project.

If you cannot determine the time of the project correctly, then you might end up overrunning it or underrunning it. This could lead to the project's failure.

What is Elapsed Time?

The elapsed time refers to the amount of time that a project has already passed since it started. It can range from days to years.

An elapsed time is used by project managers to measure how much time has passed since a particular phase or task was started. If a team member has worked on a project for two weeks, the elapsed time is two weeks.

Since the elapsed time doesn't take into account the various obstacles or delays that can happen during a project's life cycle, it should be noted that it doesn't take into account the past.

If an obstacle has slowed down the team member's progress, then their actual work hours might be higher than those indicated in the report.

Difference Between Effort, Duration, and Elapsed Time




Elapsed Time


Effort means the number of work units that must be achieved in order to complete the given work.

Duration is defined as the entire time that a project needs to be completed.

Elapsed time is known as the time required between allocating a resource to some work and completing that work.

How to measure

(Effort) = (Duration) * (Number of Resources)

Work Hours, Work Days, and Work Weeks (not including weekends or holidays)

Work Hours, Work Days, and Work Weeks (including weekends and holidays)


6 hours a day for 9 days: Effort = 54 hours

6 hours a day for 3 days: Duration = 3 days

6 hours a day for 9 days: Elapsed Time = 11 days


People unfamiliar with the terminology used in project management might have difficulty distinguishing between the time and effort involved in a project.

A waterfall approach is usually used when assessing a project or change to a service. It first identifies the main tasks and breaks them down into smaller sub-tasks. After estimating the amount of effort required to complete each task, the team usually imagines one person working on the entire project without interruptions. The duration, effort, and elapsed time are some of the components of the project-management module. Being well-equipped to manage project schedules will allow you to avoid costly errors and delays.