P Chart Maker

You can easily create a P Chart online here! Simply copy your data into the table and select the measurements.

The P Chart will then be created for you online.

Create a P Chart online

In Statistical Process Control (SPC), a P Chart is a type of control chart used to monitor the proportion or percentage of defective items or nonconformities in a process over time. It is particularly useful when dealing with data that can be categorized as either defective or non-defective, such as the number of defective products in a batch, the percentage of errors in a document, or the proportion of defective units in a production run.

How It Works:

• Data Collection: The P Chart collects data on the proportion of defective items or nonconformities observed in each sample or unit of measurement.
• Plotting the Chart: On the P Chart, the proportions of defective items or nonconformities are plotted over time or by sample number on the horizontal axis.
• Center Line and Control Limits: A center line is drawn on the chart to represent the average or mean proportion of defective items across all samples. Upper and lower control limits are also calculated based on the variability of the proportions and are typically set at a certain number of standard deviations from the center line.
• Interpreting the Chart: Similar to other control charts, when the proportions of defective items fall within the control limits and show random variation around the center line, it indicates that the process is stable and under statistical control. Any data points falling outside the control limits or showing non-random patterns suggest that the process may be experiencing special causes of variation, necessitating further investigation and corrective action.

The P Chart is commonly used in quality control and process improvement initiatives to monitor the performance of processes in terms of defect rates or nonconformity rates. By tracking the proportion of defective items over time, organizations can identify trends, patterns, and potential issues in their processes and take appropriate actions to maintain quality standards and improve overall process performance.