Significant Figures Calculator
Count significant figures, round to N sig figs, and perform arithmetic preserving correct sig figs for chemistry, physics, and engineering.
MATHCount significant figures in any number, round to a specific number of sig figs, and perform arithmetic (+ - × ÷) preserving the correct sig figs. Built for chemistry, physics, and engineering students who need to report results with appropriate measurement precision.
Sig fig rules: (1) all non-zero digits are significant; (2) zeros between non-zero digits are significant; (3) leading zeros are NOT significant; (4) trailing zeros after a decimal point ARE significant; (5) trailing zeros in whole numbers are ambiguous - use scientific notation to disambiguate. For multiplication/division, the result has the fewest sig figs of any input. For addition/subtraction, the result has the fewest decimal places of any input. Keep extra digits during intermediate steps and round only at the end.