Significant Figures Calculator
Round any number to a specified number of significant figures, identify all sig figs, and see full rounding working.
Sig figs identified in original number
What are Significant Figures?
Significant figures (sig figs) are the meaningful digits in a number that contribute to its precision. Rules: all non-zero digits are significant; zeros between non-zero digits are significant; leading zeros are NOT significant; trailing zeros after a decimal point ARE significant.
How to Count Significant Figures
In 0.00456: the leading zeros are not significant, so there are 3 sig figs (4, 5, 6). In 12300: ambiguous without a decimal point — could be 3, 4, or 5 sig figs. In 12300.: the decimal point indicates 5 sig figs.