c-Chart (Defect Count) Calculator
Calculate c-chart control limits for defect count data. Monitor the number of defects per inspection unit using Poisson-based SPC limits.
Free Six Sigma Calculators
17 toolsDPMO, Cp/Cpk, SPC charts, and sigma level calculators. Browse our free six sigma tools below — no sign-up required.
Control Chart Rules Detector
Detect SPC out-of-control conditions: points beyond 3σ, runs of 8, trends of 6, and zone violations. Apply Western Electric and Nelson rules.
Control Limits Calculator (X-bar & R Chart)
Calculate UCL and LCL for X-bar and R charts using A2, D3, D4 constants. Set up statistical process control charts for manufacturing.
Cp (Process Capability) Calculator
Calculate Cp process capability index from specification limits and process standard deviation. Assess whether your process spread fits tolerances.
Cp Index (Process Potential) Calculator
Calculate Cp index from specification limits and process standard deviation. Measure process spread potential without considering centering.
Cpk (Process Capability Index) Calculator
Calculate Cpk process capability index accounting for both spread and centering. The most-used capability metric in manufacturing quality.
DMAIC Project Savings Calculator
Calculate net savings from Six Sigma DMAIC projects by comparing before and after COPQ minus project cost. Validate improvement ROI.
DPMO Calculator (Defects Per Million Opportunities)
Calculate DPMO by dividing defects by total opportunities and multiplying by one million. Essential Six Sigma metric for process capability.
Five Why Cost Impact Calculator
Calculate the financial impact of a root cause by multiplying frequency, cost per occurrence, and duration. Justify corrective action investment.
Measurement System Analysis (MSA) Calculator
Calculate GRR percentage from repeatability and reproducibility components. Evaluate measurement system adequacy for quality decisions.
p-Chart (Proportion Defective) Calculator
Calculate p-chart control limits for proportion defective data. Monitor attribute quality with this SPC tool for manufacturing inspection.
Pp & Ppk (Process Performance) Calculator
Calculate Pp and Ppk process performance indices using overall standard deviation. Assess long-term manufacturing process capability.
Process Capability Index (Cpk) Calculator
Calculate Cpk from process mean, standard deviation, and specification limits. Evaluate whether your process meets customer requirements reliably.
R Chart (Range Chart) Calculator
Calculate R chart control limits using D3 and D4 constants. Monitor process variability with this SPC range chart tool for manufacturing.
Sigma Level Calculator
Calculate process sigma level from DPMO using inverse normal distribution plus 1.5 sigma shift. Benchmark your Six Sigma performance.
SPC Control Limit Calculator
Calculate X-bar and R chart control limits using subgroup data. Set UCL and LCL for statistical process control monitoring in manufacturing.
X-bar Chart Calculator
Calculate X-bar chart subgroup means with UCL, CL, and LCL. Monitor process centering with this statistical process control tool.