Quality & Metrology worked example

Gauge R&R Percentage at 12% acceptance threshold for percent grr: a worked example

What does the result look like when acceptance threshold for percent grr reaches 12%? The full calculation is worked below with real intermediate numbers. Use it when a measurement system analysis gives you R&R and total variation and you need a quick percent GRR for the gage acceptance decision.

The inputs for this scenario

  • Gauge R&R variation: 12 study units (unchanged)
  • Total study variation: 80 study units (unchanged)
  • Acceptance threshold for percent GRR: 12 % (raised for this scenario; the documented default is 10)

Working through the calculation

  • Applying the documented formula (Percent gauge R&R = gauge R&R variation ÷ total study variation × 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 15 % GRR for percent gauge r&r, the number this scenario is built around.
  • At this operating point the engine returns -3 points for gap to acceptance threshold.
  • At this operating point the engine returns 12 count for gauge r&r variation.
  • At this operating point the engine returns 80 count for total study variation.

How this compares with the baseline

  • Against the tool's baseline example, where acceptance threshold for percent grr sits at 10% and the headline result is 15 % GRR, this scenario lands almost exactly on the baseline at 15 % GRR.
  • A figure at this level is achievable when acceptance threshold for percent grr is genuinely sustained, not just peaked for a shift. It assumes you already have valid variation figures from a proper crossed study; the AIAG rule of thumb (under 10% good, 10-30% conditional, over 30% unacceptable) is a guideline, not a hard pass-fail, and %GRR can be inflated by too few parts or too narrow a part range.

Results at a glance

  • Percent gauge R&R: 15 % GRR (headline result)
  • Gap to acceptance threshold: -3 points
  • Gauge R&R variation: 12 count
  • Total study variation: 80 count

Run it with your numbers

  • Every input above is editable in the live Gauge R&R Percentage calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.