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Free Software:


Is a utility for use with industrial PT100 resistance thermometers, can use standard or custom coefficients and calculate R to T or T to R. Windows 3.1 or higher.

Uncertainty Calculator

New - March 2002 V3.2


Revision 3.0

Initial Win 2000 release

Revision 3.1

'Type A' entry is no longer required i.e. only Type B uncertainty components can be computed without any Type A components.

Variances computed as square of Standard Uncertainty rather than compiled RMS (variance computation change does not effect previously computed combined Std Uncertainty or Expanded Uncertainty calculations).

Revision 3.2

Bug fixed with computing negative correlations coefficients (negative correlations sign was not carried through the calculations such that negative correlations were calculated as positive correlations).

A new Option (see Option Menu) that normalizes Type A and B Standard Uncertainty & Variance RMS results to 1 Sigma (1 Std Deviation) - does not affect Type A and B Combined RMS results.

New Sample Statistic functions that computes Standard Error of the Means and Coefficient of Variation. On-line manual HELP file appendix omitted for faster on-line loading. Revision history added to on-line manual.


The "Uncertainty Calculator" is a "FREEWARE" software program designed to compute and express measurement uncertainty in a simple, straightforward manner, congruent with the basic guidelines contained within the following publications:

  • ISO "Guide to the Expression of Uncertainty in Measurement", 1993
  • NIST Technical Note 1297, "Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results", January 1993
  • NCSL Recommended Practice RP-12, "Determining and Reporting Measurement Uncertainties", April 1995
  • ANSI/NCSL Z540-2-1996, "American National Standard for Expressing Uncertainty - U.S. Guide to the Expression of Uncertainty in Measurement"
Download! Version 3.2        Disclaimer

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