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Employee Retention Rate Calculator

Compare employees retained from the original group with that group's starting size. Use a consistent review period and treatment of transfers or rehires; new hires do not count as retained cohort members.

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Your numbers

Your figures stay on this device.

How the calculation works

Retention follows a defined starting group of employees and asks how many of those same people remain at the end. It deliberately excludes new hires, so growth in total headcount cannot disguise departures from the original cohort.

Retention = employees from the original cohort still present ÷ original cohort size × 100.

  1. Fix the starting cohort

    Identify the people present at the beginning under a consistent definition. Decide how transfers or rehires will be treated before comparing periods.

  2. Count surviving cohort members

    Match the ending records back to that original group. Later hires do not increase the retained numerator simply because they are employed at the end.

  3. Calculate retention and departures

    Divide retained members by starting members and multiply by one hundred. Subtracting retained from starting count also shows how many cohort members left.

Worked example: Retention

Sample inputs demonstrate the method. They are not a forecast or product offer.

The first example starts with 100 cohort members and retains 92 of those same people. Dividing 92 by 100 gives 92% retention. The separate count of cohort members who left is eight, regardless of any new hires.

Employees in the starting cohort
100
That same cohort still employed at the end
92

Expected result

Cohort retention rate
92%
Worked example: All retained

Sample inputs demonstrate the method. They are not a forecast or product offer.

Employees in the starting cohort
10
That same cohort still employed at the end
10

Expected result

Cohort retention rate
100%

Understanding your result

A 100% result means every member of the defined cohort remains. Zero means none remain, even if replacements have maintained or expanded the overall headcount.

Retention is not automatically one hundred minus a general turnover rate. Turnover normally uses all departures and an average workforce denominator, whereas this tool tracks a fixed cohort.

Questions you might have

What does this employee retention rate calculator include?

Measure how much of a starting employee cohort remained at the end of your review period.

Which assumptions should I check?

New hires are not part of the starting cohort. Define transfers, rehires and the review period consistently.

Choosing the right inputs

Employees in the starting cohort
Enter the positive whole number of employees in the original cohort. Record the review period and population definition before counting.
That same cohort still employed at the end
Count only members of that original cohort still included at the end. This must be a whole number from zero up to the starting count, not the organisation’s complete ending headcount.

Common mistakes to avoid

  • Do not substitute total ending headcount for the number retained from the starting group.
  • Changing the treatment of transfers or rehires between periods changes the meaning of the retention comparison.

Assumptions to check

  • New hires are not part of the starting cohort. Define transfers, rehires and the review period consistently.

Sources and method

Read our calculation and testing approach.