WSJF calculator

How WSJF is calculated

Weighted Shortest Job First is the prioritization method used in the Scaled Agile Framework (SAFe), based on Don Reinertsen's work on the economics of product flow. It ranks work by how much value is lost per unit of time while it waits, divided by how long it takes. Cost of delay is the sum of three relative scores: user or business value, time criticality (does the value fall off if it ships later, is there a deadline) and risk reduction or opportunity enablement. WSJF = cost of delay ÷ job size. Each factor uses the modified Fibonacci scale 1, 2, 3, 5, 8, 13, 20, whose widening gaps reflect the growing uncertainty of large estimates.

Example: a feature with business value 8, time criticality 5 and risk reduction 3 has a cost of delay of 16. With a job size of 5, WSJF = 16 ÷ 5 = 3.2. The same cost of delay on a job of size 2 would score 8, so a smaller job with the same urgency jumps ahead.

Ranked by WSJF, the logging cleanup goes first and the redesigned dashboard last, although the dashboard has the second-highest value on its own.

Scoring WSJF well

The scores are relative, not absolute. The usual practice is to score one column at a time across all items: find the item with the lowest business value, give it a 1, and rate the others against it, then do the same for time criticality, risk reduction and size. Scoring a single item in isolation produces numbers that cannot be compared.

Job size is a proxy for duration. If a large job can be split so that the most valuable part ships first, its WSJF usually rises, which is exactly the behavior the method is meant to encourage. Be careful with time criticality: inflating it for every item flattens the ranking. Reserve high values for real deadlines, contracts or market windows. Re-score the backlog every planning cycle, because cost of delay changes as deadlines approach and as other work lands.