Sigma Level to Percentage Calculator



Formula

The formula to convert a Sigma Level (σ) to a percentage is:

\[ P = \left(1 - \left(\frac{1}{10^{\left(\frac{\sigma}{3}\right)}}\right)\right) \times 100 \]

Where:

What is Sigma Level?

Sigma level is a statistical term that measures the capability of a process to perform defect-free work. A higher sigma level indicates a higher percentage of products or services without defects. It is commonly used in Six Sigma methodologies to quantify the quality of a process.

Example Calculation

Let's assume the following:

Step 1: Calculate the percentage:

\[ P = \left(1 - \left(\frac{1}{10^{\left(\frac{6}{3}\right)}}\right)\right) \times 100 = \left(1 - \left(\frac{1}{10^2}\right)\right) \times 100 = \left(1 - \frac{1}{100}\right) \times 100 = 99\% \]

Therefore, the percentage of the process that is defect-free at a sigma level of 6 is 99%.