Get the most from every feature
Step-by-step guides for MetTutor’s training modules, practice tools, and professional calculators — so you can focus on the work that matters.
Tools
The SI Unit Converter converts one value between two units of the same quantity, across 24 unit domains, using exact factors built from the unit definitions.
The TAR Calculator divides a DUT’s ± tolerance by the ± accuracy of the standard, shows the ratio truncated to two decimals, and places it against the legacy 4:1 rule.
The TUR Calculator (Simplified) divides a DUT tolerance by the 95 % expanded uncertainty of the calibration, places the ratio against 4:1, and gives the Method 6 guard band when 4:1 is not met.
The TUR Calculator (Full ANSI/NCSL Z540.3) computes the test uncertainty ratio, then the probability of false acceptance (PFA) and false rejection (PFR) for four guard band options, judged against the 2 % PFA limit.
The Type B Uncertainty Estimator turns a stated limit — a half-width, a span, a resolution or a manufacturer’s specification — into a standard uncertainty u, using the distribution you choose.
The GUM Uncertainty Budget Calculator turns a list of uncertainty contributors into u_c, ν_eff, k and a reported expanded uncertainty U, computed exactly in code.
The Decision Rules & Guard Band Calculator decides whether one measured value conforms to a symmetric tolerance, under the decision rule you choose, and compares that verdict with three other rules.
The Welch-Satterthwaite Effective DOF calculator combines two or more uncertainty contributions, computes the effective degrees of freedom by GUM G.4.1, reads the coverage factor from Table G.2 and reports the expanded uncertainty.
