X̄-R Control Chart Online
Online X̄-R (average and range) control chart tool. Automatically calculates control limits, plots the chart and checks the 8 out-of-control rules. Supports CSV data import.
When should an X̄-R control chart be used?
It applies to variables data with subgroup sizes of 2 ≤ n ≤ 10. When the subgroup size exceeds 10, use an X̄-S control chart instead.
What are the 8 out-of-control rules?
They include eight patterns such as: one point beyond 3σ, nine points in a row on the same side of the center line, six points in a row steadily increasing or decreasing, and fourteen points in a row alternating up and down.