PERT Calculator

Plan your personal and work-related projects efficiently with the help of this online PERT calculator.

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Optimistic:

Pessimistic:

Most Probable:

Desired Completion:

PERT Estimate Unit:

Standard Deviation Unit:

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With the help of this PERT calculator, you can find out the expected completion time of a project, the standard deviation, and the chance of completing the project in the desired time frame. This handy tool is solely designed to help the contractors find the expected time duration for the completion of a project so that they can provide the correct estimation about the completion of a project.

Understanding PERT:

PERT (Program Evaluation and Review Technique) is a way of calculating the time required for the completion of a project and it determines a Critical Path Method variation (CPM). It is helpful in scheduling all the tasks and also helps in defining the right project completion time for the client. This calculation includes the following estimations:

Optimistic:

Estimation of all the conditions without any risks.

Most likely:

It includes both favorable and unfavorable conditions.

Pessimistic:

This estimation includes all the negative risks.

How To Calculate PERT?

Have a look at the following PERT method formula to calculate this parameter manually:

PERT Formula:

\(T_{E}\) = (O + 4M + P) / 6

Standard Deviation (SD) Formula of PERT:

SD = (P - O) / 6

Where,

\(T_{E}\) represents the Pert Expected Time Duration
O is the optimistic estimation
P shows the pessimistic estimation
M is the most likely estimate
SD is the representative of the standard deviation

If it seems difficult to calculate the PERT manually, then for PERT estimating get the help of a pert calculator. It will allow you to perform precise calculations effortlessly.

PERT Calculation Example:

Let's suppose there is a contractor who is expected to complete a project in 2 years and has the following estimations:

Optimistic Estimate (O) = 14 months
Most Likely Estimate (M) = 16 months
Pessimistic Estimate (P) = 22 months

Now how to calculate PERT?

Solution:

Given that:

O = 12 months

M = 18 months

P = 24 months

Put these values in the PERT estimation formula:

T_E = (O + 4M + P) / 6

T_E = (14 + (4 x M) + P) / 6

T_E = (14 + (4 x 16) + 22) / 6

T_E = (14 + (64) + 22) / 6

T_E = (14 + 64 + 22) / 6

T_E = 100 / 6

T_E = 16.67

Now,

SD = (P - O) / 6

SD = (22-14) / 6 = 8 /6

SD = 1.33

According to this, the contractor will be able to complete the work in 16.67 months with a standard deviation of 1.33 months. Check out more pert formula examples to make the concept clear in your mind so that you can perform the manual calculation correctly.

Working of PERT Calculator:

Get the assistance of our easy-to-use PERT formula calculator to estimate PERT in no time. Let's see how it works!

Inputs:

Add the values of “Optimistic Estimate”, and “Most Likely Estimate”
Likewise, enter the “Pessimistic Estimate”, and “Desired Completion Time” in the specified fields
Set the required “PERT” and “Standard Deviation” units
Tap on the “Calculate” button

Output:

PERT
Standard Deviation
Probability of Completion

FAQ’s:

What Are The Six 6 Steps In PERT?

Requires to identify all the defined activities
Understanding the way or sequence in which the activities have to be performed
Creation of network diagram
Know the critical path
Estimate of time for the completion of each task
Changing and updating of the PERT Chart

What Are The Benefits of PERT Estimation?

PERT is very useful in making the right plan for managing all the tasks of a project efficiently. Let's take a look at the below-mentioned benefits of PERT calculation:

Helps in evaluating the time and resources
Informs about the requirements of all activities
Allows to anticipate the actions in a project
Helps to account for the uncertainty

What Is The 4 In The PERT Formula?

The digit 4 in the PERT estimate formula shows that we are estimating the PERT by considering the factor of 4 and getting the average of the weighted most likely time, including the best and worst scenarios.