This tool, The Significant Figures Calculator , lets users compute and edit significant figures. The tool is based on the theory of relative errors and reports results in conventional and scientific notation. Values involving ambiguous trailing zeros are properly counted. A handy tool for teachers and students, and for those that need to report quantities to a given number of significant figures. Giving a precise definition for the correct number of significant figures is quite subtle ( Higham, 2002 ). Different rules for counting significant figures have been reported. There is also the fact that not all significant figures are meaningful figures. The theory of relative errors can be used to derive safe counting guidelines. See Numerical Analysis , by Burden and Faires, pages 20-22. According to the theory, it can be stated that significant figures can be attributed only to measured quantities for which a relative error can be computed.…