Significant Figures Significant Figure Rules Nonzero integers - nonzero integers always count as significant figures. These do not count as significant figures. In the number 0.0025, the three zeros simply indicate the position of the decimal point. This number only has two significant figures.
Captive zeros are zeros between nonzero digits.
These always count as significant figures. The number 1.008 has four significant figures. Trailing zeros are zeros at the right end of the number. They are significant only if the number contains a decimal point. The number one hundred written as 100. also has three signficant figures.