Weighted Shortest Job First (WSJF) is an agile prioritisation model, central to the Scaled Agile Framework (SAFe), used to sequence work for maximum economic benefit by balancing Cost of Delay against Job Duration.
The method calculates a priority score for backlog items using the formula:
WSJF = Cost of Delay / Job Size
Cost of Delay is a composite metric comprising three weighted factors:
User/Business Value: The importance of the task to users and potential revenue impact.
Time Criticality: The urgency of the task and the rate at which value decays over time.
Risk Reduction/Opportunity Enablement: The task's ability to mitigate future risks or seize new opportunities.
Job Size represents the relative effort or duration required to complete the item, typically estimated using a modified Fibonacci sequence (e.g., 1, 2, 3, 5, 8, 13, 21) to ensure consistent, relative comparisons. By prioritizing items with the highest WSJF scores, agile teams ensure they deliver the highest value in the shortest time, minimizing waste and optimizing return on investment.