Attrition Rate Calculator
An attrition rate calculator measures how many employees leave over a period. Enter the headcount at the start and end of the period and the number of people who left to get your attrition rate, retention rate and average headcount.
At a glance
How the attrition rate calculator works
- 1 Enter the number of employees at the start of the period.
- 2 Enter the number at the end of the period.
- 3 Enter how many employees left during the period.
- 4 The calculator uses average headcount to give an accurate attrition and retention rate.
Average headcount = (Start + End) ÷ 2. Attrition rate % = Leavers ÷ Average headcount × 100. Retention rate % = 100 − Attrition rate.
Frequently asked questions
How do you calculate attrition rate?
Divide the number of employees who left during the period by the average headcount, then multiply by 100. Average headcount is the starting count plus ending count divided by two — this avoids distortion when the company is growing or shrinking.
What is the difference between attrition and turnover?
They are often used interchangeably. Strictly, turnover counts all departures (including backfilled roles), while attrition sometimes refers to roles left unfilled. Both are measured as departures ÷ average headcount × 100.
What is a healthy attrition rate?
Around 10% or below per year is generally considered healthy, though it varies by industry. Rates above 20% usually warrant investigation into pay, management, workload or career growth.
Why use average headcount instead of starting headcount?
Using the average smooths out growth or contraction during the period, so a company that doubled in size is not credited with an artificially low rate. It is the standard denominator in HR analytics.