What is attrition rate?
Attrition rate measures the percentage of employees who leave an organization over a given period, whether through resignation, retirement, or termination. It’s a key metric for HR planning and workforce analysis.
How this calculator works
Enter the number of employees who left during the period, along with your headcount at the start and end of that period. The calculator averages the start and end headcounts, then divides the number who left by that average to compute the attrition rate.
This is a general HR analytics tool for planning purposes and does not account for seasonal hiring patterns or specific departure reasons.
Last reviewed August 2026