Significant Figures Calculator
Enter a number or an expression (e.g., 5.13*3.78)
Results
Decimal notation:
Number of significant figures:
Number of decimals:
Scientific notation:
E notation:
Step-by-step output
SF = significant figure
References
  • All non-zero digits are significant.
  • Zeros between non-zero digits are significant.
  • Leading zeros before the first non-zero digit are not significant.
  • Trailing zeros are significant only when there is a decimal point.
  • Rounding uses “half-up” (5 rounds up).
  • Add/Subtract → round the final result to the fewest decimal places among inputs.
  • Multiply/Divide → round the final result to the fewest significant figures among inputs.

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