Upper Control Limit Calculator

How to Calculate Upper Control Limit

Calculating the upper control limit can be done with the following variables:

• Control mean


• Control standard deviation


• Control limit to evaluate

• UCL = Upper control limit


• CM = Control mean


• CSD = Control standard deviation


• CLE = Control limit to evaluate

Understanding Your Results

When you use this tool you will get two different results. First, you will see your upper control limit value. This is the highest acceptable value for your specific situation. Aside from that, you will get your lower control limit. Which is essentially the same thing in concept, but it is referring to the lowest acceptable value based on your entry.

How to Use the Upper Control Limit Tool

Finding the upper control limit value can be done with a bit of work, or by simply using this tool. Plugging in a few values into this tool can make calculating the upper control limit easier than ever. The steps involved with using this tool include:

1. Enter the control mean value.


2. Enter the control standard deviation.


3. Enter the control limit to evaluate, or the amount of padding you are willing to apply around your value.


4. Hit the calculate button and instantly get your results.

Calculation Example

A coffee shop wants to ensure its baristas pour consistent amounts of coffee into cups to maintain quality and customer satisfaction. The shop uses a process control chart to monitor the volume of coffee poured into medium-sized cups. The control mean, or average, pour amount is 350 ml and the standard deviation is 5 ml. We can use this tool to determine the UCL. We can enter 350 into the control mean field, 5 into the control standard deviation field, and leave the control limit to evaluate as 3. If we wanted to allow for more than 3 standard deviations from the mean we can change this number to reflect that amount, but we are fine with 3 in this situation. We can now hit calculate and get a UCL of 365 ml and a LCL of 335 ml.