Staff Turnover Calculator
Turnover and retention rates, with voluntary and involuntary separated — because they mean opposite things.
Turnover is leavers divided by average headcount over the period.
How the staff turnover calculator works
Turnover is leavers divided by average headcount over the period. Using average headcount rather than starting or ending headcount matters in a growing team: a company that doubled in size would otherwise report a flattering figure simply because the denominator grew.
The split is what makes the number useful. Voluntary turnover — people choosing to leave — is a signal about management, pay and work. Involuntary turnover is a signal about hiring and performance management. A combined figure of 20% means completely different things depending on which way it splits.
The stability index is the complement worth watching: the share of staff with more than a year's service. High turnover concentrated among new starters is a different problem from turnover among experienced staff, and the two figures together tell you which you have.
Formula: turnover = leavers / average headcount × 100
Worked examples
| Inputs | Turnover rate | Note |
|---|---|---|
| 42 leavers from an average of 250 | 16.8% | 16.8% turnover |
| Mostly involuntary | 16.8% | a hiring problem, not a retention one |
| A six-month period | 16.8% | annualised to the same rate |
FAQFrequently asked questions
How do I calculate staff turnover?
Leavers divided by average headcount over the period, annualised. Average headcount matters if the team grew or shrank.
Why separate voluntary from involuntary?
Because they mean opposite things. Voluntary departures point at pay, management and the work; involuntary ones point at hiring and performance management.
What is a good turnover rate?
It varies enormously by sector — hospitality and retail routinely exceed 50%, professional services often sit near 10%. Compare against your own history and your industry.
What is the stability index?
The share of staff with more than a year of service. High turnover concentrated among new starters is a different problem from losing experienced people.
Should I include fixed-term contracts ending?
Only if you count them in headcount. Whatever you decide, be consistent, or the series is meaningless.
Where these figures come from
- CIPD — Employee turnover and retention factsheet — the turnover and stability index definitions used here
- Acas — the UK workplace advice service
Last checked: September 2026. These are standard management definitions; where practice varies, the page says which convention it uses.