Measurement Uncertainty Calculator
Enter the known values and run the calculation.
Overview
Estimate combined uncertainty so a result can be discussed in calibration-aware, laboratory-grade terms.
Use this tool to combine independent standard uncertainty contributors by root-sum-square and then apply a coverage factor for expanded uncertainty.
It is aimed at calibration and high-trust measurement work where a result needs more than just a nominal number.
The math and how it's used
Combined standard uncertainty is uc = sqrt(u1^2 + u2^2 + ... + un^2) for independent contributors.
Expanded uncertainty is U = k * uc, where k is the selected coverage factor.
Use this to combine a handful of standard uncertainty terms into one quick expanded-uncertainty result.
It is meant for the common case where the contributors are already expressed in compatible units and can reasonably be combined by root-sum-square. Correlation and distribution conversions still belong in the full uncertainty budget.
Scope of the result
This tool assumes the listed contributors are already standard uncertainties in the same units and are independent enough to combine by RSS.
If correlation, drift models, or distribution conversions matter, keep those steps in the full uncertainty budget outside this quick tool.