What is Weighted Shortest Job First & How to Calculate it?

What Is Weighted Shortest Job First (WSJF)

Weighted shortest job first or WSJF is a tool for prioritizing a task. It’s a calculation to determine whether it is profitable to work on a specific task over another task at a given time. So what determines the situation that we are talking about? 

The situation can be the urgency of performing a task.

It can be any specific challenge that might force a team to rethink whether to proceed with a given task or to delay it for a while and focus on some other task that might yield better results.

WSJF is a mathematical calculation of risk involved in dropping a task for later or picking up a task for the current situation over any other task by comparing the cost of delay with job duration.

How To Calculate WSJF Score?

The WSJF calculation involves-

Cost of Delay (CoD)

Cost of delay is a relative score that is calculated by the score of the following three factors:

• User/Business Value

How valuable a job is for the customer. Like the one with more significant revenue generation or higher customer appeal will be rated increased.

• Time Criticality

Is there any significant change in the user/business value over a particular period that may alter our market? Or competitiveness.

• Risk Reduction/Opportunity Enablement Value

This involves future consequences associated with each job.

CoD is calculated by adding the above scores.

Job Duration or Job Size

It is a relative measure of time involved in the tasks being compared. We aren’t using the direct value of time because that would mess up the calculations. The team assigns a score to each task. Job size is the estimated amount of work to be done to complete a task.

Now we know about these two terms that will create the formula for our weighted shortest job first calculation, and it is the ratio of the cost of delay to job duration.

WSJF Formula

You can note a few things from this: The cost of delay is directly proportional to the WSJF score, meaning that you shall prioritize a task with a higher cost of delay. 

Similarly, the job duration has an inversely proportional relation with WSJF. 

If a task consumes way less time, you shall prioritize it high as it is easy to complete and shed the workload.

So a balance between these two provides us with a clearer picture of prioritization.

Implementing WSJF Results

Any team or team member can apply this method to weigh each task’s importance and set priorities likewise after studying the results.

It helps to find a solution whenever there is a conflict between multiple projects on the roadmap that you are required to work on.

For instance, the development team can use the figures to determine whether they should add a particular feature as soon as possible or if they can pause and work on a different feature that the competitors could be launching soon.

What Is an Example of WSJF?

Let’s look at the WSJF calculation example to understand the topic better. 

Suppose you score one initiative on the list. And the cost of delay is nine, and job duration is 1. The WSJF score of this initiative will be either 1 or 91. 

Another WSJF calculation example is that if you have another initiative with the cost of delay at the score of 7 and the job duration at 4, then the WSJF score of that intuitive will be 1.75 or 74.

Notice how higher cost delays have a top ranking on the weighted shortest job first list. Also, the job duration score initiatives got a higher position on the WSJF list. 

How to Prioritize Items on a Product Roadmap Using Weighted Shortest Job First?

When your product roadmap is flooded with initiatives that require time and resources, the weighted shortest job first comes to the rescue. 

With the help of this article’s how-to calculate WSJF score method, you can determine a score for each product backlog item. Follow this by selecting the highest scoring items and placing them at the top of the product roadmap. 

What Are the Alternatives of WSJF?

Among the prioritization tools, WSJF is considered the most efficient in terms of product, data-driven prioritization, sequencing and planning, and more. 

However, what beats all of this is that the weighted shortest job first prioritization takes the product teams’ time. Hence teams start searching for the alternatives of the weighted fastest job first and tools that will give them quicker results. 

The good WSJF alternatives are the value vs. effort, MoSCoW, and the Eisenhower matrix. These tools are quick ways to prioritize your features into different sections. 

You can use the value vs. effort tool when you have a lot of features.