Significant Figures Calculator

Count significant figures or round numbers based on significant digits. Enter any number including scientific notation (e.g., 3.1415e5).

Understanding Significant Figures

Rules for Significant Figures

  • • All non-zero digits are significant (1234 has 4 significant figures)
  • • Zeros between non-zero digits are significant (1002 has 4 significant figures)
  • • Leading zeros are not significant (0.00123 has 3 significant figures)
  • • Trailing zeros after a decimal point are significant (123.400 has 6 significant figures)