Developed at Bradford University in the 1980s, the Bradford factor highlights frequent short-term absence, which tends to disrupt work most. Ten one-day absences score 1,000, while one ten-day absence scores only 10. Use it to start a conversation, not as an automatic trigger – absences linked to disability or pregnancy should be excluded.
How to use the Bradford Factor Calculator
- Number of absence spells
- Total days absent
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the number of separate absence spells and the total days absent in the last 52 weeks.
Tips
- Use figures for the same period (a month, a quarter or a year) for every input so ratios compare like with like.
- Track the metric over time – the trend usually tells you more than a single value.
- Compare your result with industry benchmarks, which vary a lot between sectors.
- Treat the result as a starting point for a decision, then check the assumptions behind each input.
Common mistakes to avoid
- Mixing monthly and yearly numbers in the same calculation.
- Using revenue where the formula needs profit (or the other way round).
- Forgetting hidden costs such as taxes, fees, overheads or your own time.
Inputs explained
| Field | What to enter |
|---|---|
| Number of absence spells | A number |
| Total days absent | A number |
Example values
How the main result changes when Number of absence spells changes and everything else stays at the example values above:
| Number of absence spells | Bradford factor |
|---|---|
| 2 | 24 |
| 3 | 54 |
| 4 | 96 |
| 5 | 150 |
| 6 | 216 |
| 8 | 384 |
Formula
Bradford factor B = S² × DS = number of separate spells of absence; D = total days absent (usually over a rolling 52 weeks)Worked example
Inputs — Number of absence spells: 4; Total days absent: 6.
Results — Bradford factor = 96; Typical policy level = Verbal warning level (51–200).
Frequently asked questions
How is the Bradford factor calculated?
Spells squared times total days: 4 spells and 6 days give 16 × 6 = 96.
What is a high Bradford score?
Many policies act at 51, 201, 401 and 651 points; thresholds vary by employer.
Is the Bradford factor fair?
It can disadvantage people with long-term conditions, so use it with discretion.
What formula does the Bradford Factor Calculator use?
Bradford factor B = S² × D.