Attrition Rate

Used when leaders want the “chose to leave” signal separate from layoffs or involuntary exits.

Attrition % = (voluntary leavers ÷ average headcount) × 100.

Tip: Keep “Voluntary Separations” and “Average Headcount” on the same basis (units, period, and definition) before you calculate.

Cluster: HR hub · Professional KPIs · Percentage guide

Attrition rate focuses on voluntary exits relative to average headcount.

Enter voluntary separations and average headcount for the same period.

Employees who chose to leave
Average employees during the period

Attrition Rate

Understanding Attrition Rate

How we calculate. Attrition % = (voluntary leavers ÷ average headcount) × 100. See our methodology and accuracy policy .

Real-world scenario: A typical Attrition Rate case uses voluntary separations 18 and average headcount 200. Enter the same figures below to reproduce the worked path.

What is Attrition Rate?

Used when leaders want the “chose to leave” signal separate from layoffs or involuntary exits.

  • Voluntary only unless your org defines attrition differently
  • Same denominator as turnover for apples-to-apples
  • Retirement policies may or may not count as attrition

The Formula

Attrition Rate
Attrition % = (Voluntary separations ÷ Average headcount) × 100

Worked Example

Scenario: 18 voluntary leavers with average headcount 200.
Step 1: Voluntary = 18
Step 2: Avg = 200
Step 3: Attrition = (18 ÷ 200) × 100 = 9%
Answer: Attrition rate is 9%.

Common Use Cases

  • Engagement programs: track regrettable exits
  • Location compare: site-level attrition
  • Role heatmaps: hard-to-retain jobs

Pro Tips

  • Tag regrettable vs non-regrettable
  • Watch new-hire attrition separately
  • Don’t mix FY calendars across regions
ScenarioWhen to use
Percent of a numberFinding a part of a whole (tax, tip, score)
Percent changeComparing old vs new values

Limitations: Attrition Rate results are educational HR planning aids—not legal, payroll, or employment advice. Confirm definitions with your HR/finance policies.

Common mistakes

  • Swapping part and whole: The denominator must be the full total, not a subset.
  • Rounding too early: Carry extra decimal places through multi-step work before rounding the final percent.
  • Mixing percent and decimal forms: Enter rates in the format the calculator labels expect.

The worked example for attrition rate was verified with the calculator form on this page—enter the same values to confirm the result.

When to use this calculator

  • Use this page when your wording matches attrition rate and the form labels on screen.
  • Use percent of a number for “what is X% of Y?” problems.
  • Use number is what percent when you know part and whole and need the percent.

Still unsure about attrition rate? Start with the quick answer above, then open the linked calculator that matches your wording.

Frequently Asked Questions

How do I use this attrition rate calculator?

For attrition rate, enter the values labeled on the form, then press Calculate. Compare the result to the worked example on this page.

What formula does this page use?

See the quick answer and formula box above for attrition rate—the same percentage calculator expression is applied to your inputs.

What if my result looks wrong?

When checking attrition rate, re-check part vs whole (or rate vs base), rounding, and whether percents were entered as 25 rather than 0.25 when the form expects percents.

Authoritative References

For people-analytics definitions, consult:

  • SHRM — HR metrics and workforce standards
  • ISO 30414 — human capital reporting guidance
  • U.S. BLS — labor statistics context