Significant Figures Calculator
Count and round significant digits following standard scientific rules.
Enter a number to count its significant figures.
About Significant Figures
Significant figures (also known as the significant digits, precision or resolution) of a number in positional notation are digits in the number that are reliable and absolutely necessary to indicate the quantity of something.
This calculator helps you identify which digits in a number are significant based on standard scientific rules and can also round numbers to a specific number of significant figures.
The Rules
- 1Non-zero digits are always significant.
- 2Any zeros between two significant digits are significant.
- 3Leading zeros are not significant.
- 4Trailing zeros in a number containing a decimal point are significant.