Round any number to a given number of significant figures. Shows step-by-step working, scientific notation output, and rules for identifying sig figs.
Meaningful digits in a measurement. Non-zero digits are always significant. Leading zeros never are. Trailing zeros after a decimal are significant.
Three: 4, 5, and the trailing zero. Leading zeros are placeholders.
They communicate precision. 5.00 cm means measured to the nearest hundredth. 5 cm means to the nearest whole unit.
When multiplying or dividing, use the same sig figs as the least precise input.
Decimal places count digits after the decimal point. Significant figures count from the first non-zero digit.