Bradford Factor Calculator
Calculate the Bradford Factor score for employee absence management.
Used by HR departments worldwide to identify patterns of short, frequent absences.
What Is the Bradford Factor? The Bradford Factor (also called the Bradford Formula) is a human resources tool used to measure employee absenteeism, with particular emphasis on short, frequent, unplanned absences. It was developed at the Bradford University School of Management in England in the 1980s.
The Formula Bradford Factor = S x S x D. Where S = the number of separate absence spells (instances) in a rolling period, and D = the total number of days absent in that period. The spell count is SQUARED, which means frequent short absences score much higher than a single long absence.
Why S Is Squared The theory is that frequent short absences are more disruptive to a business than one long absence. When an employee takes many 1-day absences, the team must repeatedly reorganize, redistribute work, and adjust schedules. A single extended absence allows the team to plan and arrange temporary cover.
Score Interpretation 0-49: Green zone — acceptable absence levels. 50-124: Amber zone — absence is above average and should be monitored. 125-399: Red zone — absence is a concern, formal review may be needed. 400-649: Serious concern — formal action typically required. 650+: Very high — immediate action usually taken.
Example Comparison Employee A takes 1 absence of 10 days: BF = 1 x 1 x 10 = 10. Employee B takes 10 absences of 1 day each: BF = 10 x 10 x 10 = 1,000. Same total days absent, but Employee B’s score is 100 times higher because the pattern of frequent short absences is considered more disruptive.
Rolling Period Most organizations calculate the Bradford Factor over a rolling 52-week period. Some use 12 months from a fixed start date. The score resets as old absences fall outside the rolling window.
Limitations The Bradford Factor does not distinguish between types of absence (illness vs personal). It can penalize employees with chronic health conditions. Many organizations use it as one of several indicators rather than a sole decision-making tool. It should always be used alongside occupational health advice.