Quality & Metrology worked example

Measurement Uncertainty with instrument or gauge uncertainty of 0.01 measured units: a worked example

This worked example runs the measurement uncertainty numbers for a tougher week than the baseline: instrument or gauge uncertainty of 0.01 measured units instead of the typical 0.01 measured units. Add the contributors in a measurement uncertainty budget to estimate the total uncertainty for a measurement.

The inputs for this scenario

  • Instrument or gauge uncertainty: 0.01 measured units (the input this scenario stresses; the baseline uses 0.01)
  • Repeatability (equipment) contribution: 0.01 measured units (held at the documented default)
  • Reproducibility (appraiser) contribution: 0.01 measured units (held at the documented default)
  • Environmental and other contribution: 0 measured units (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Total measurement uncertainty = instrument + repeatability + reproducibility + environmental.
  • Total measurement uncertainty works out to 0.03 units at these inputs, and this is the headline figure for the scenario.
  • Element 1 works out to 0.01 units at these inputs.
  • Element 2 works out to 0.01 units at these inputs.
  • Element 3 + 4 works out to 0.01 units at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where instrument or gauge uncertainty sits at 0.01 measured units and the headline result is 0.03 units, this scenario comes in 7.14% below the baseline at 0.03 units.
  • Use it when building a measurement uncertainty budget for a gauge or process, or when a customer or accreditation body asks for stated uncertainty. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Total measurement uncertainty: 0.03 units (headline result)
  • Element 1: 0.01 units
  • Element 2: 0.01 units
  • Element 3 + 4: 0.01 units

Run it with your numbers

  • To rerun this with your own numbers, open the live Measurement Uncertainty calculator, set instrument or gauge uncertainty to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.