Free calculators
Everything runs in your browser; nothing you type is sent anywhere. Each calculator was checked against published examples before release.
Cp / Cpk / Pp / Ppk
Paste readings (in production order) or enter a mean and standard deviation. Leave a spec limit blank for one-sided specs.
With readings: within sigma = average moving range / 1.128 (I-MR method); overall sigma = sample standard deviation. Expected ppm assumes a normal distribution. Check a control chart first: capability of an unstable process means little. What's a good Cpk?
AQL sample size
Assumptions: single sampling, normal inspection (not tightened or reduced), general inspection levels I-III, AQL in percent nonconforming up to 10. Code letters and sample sizes follow MIL-STD-105E (a public-domain U.S. military standard; ANSI/ASQ Z1.4 uses the same plans). Where the table shows an arrow, the calculator uses the plan the arrow points to. If the sample is as large as the lot, inspect 100%. Use your customer's required plan and the official table for contract acceptance; switching rules are not applied.
Quick Gage R&R (average and range method)
Pre-filled with the widely published reference example for this method (result: %GRR about 26.7%, ndc 5). Bands: under 10% acceptable, 10-30% conditional, over 30% not acceptable (common guideline). For full studies with range checks use the Gage R&R pack.
CMMC / NIST 800-171 SPRS score
Set each requirement. The score updates as you go.
| ID | Requirement (NIST SP 800-171 Rev 2) | Pts | Status |
|---|
Point values from the DoD Assessment Methodology v1.2.1: start at 110, subtract 5/3/1 per requirement not met; partial credit only for 3.5.3 (MFA) and 3.13.11 (FIPS encryption). This is a self-check, not an assessment or legal advice. Confirm current CMMC rules. CMMC in plain English