Process Rate

Process rate is the inverse of process time. If it takes 30 minutes to process one unit, the process rate is 2 units per hour. It tells you the speed at which a single work center produces output.

Process rate and process capacity are usually the same value for a single work center. They diverge when resource availability, parallel work centers, or quality issues come into play.

Formula

r = Time unit / Process time

For an hourly rate: r = 60 / p (where p is in minutes)

Example

A data entry clerk processes one form in 12 minutes. Process rate = 60 / 12 = 5 forms per hour.

If there are two clerks doing the same work (parallel), the combined process rate = 5 × 2 = 10 forms per hour, but each clerk’s individual process rate is still 5.

Why It Matters

Process rate is how you compare the speed of different steps in a process. The step with the lowest process rate is the bottleneck, it limits the entire process. When evaluating improvement options, increasing the rate at the bottleneck has the highest impact; increasing it elsewhere won’t change overall output.