How Many Significant Figures Are in 1.2300?
1.2300= 5 significant figures
Why 1.2300 has 5 sig figs
1.2300 has a decimal point and ends in two trailing zeros. Since the trailing zeros come after a decimal point, they are always significant. The digits 1, 2, 3, 0, and 0 are all significant, giving exactly 5 sig figs. Writing 1.2300 instead of 1.23 explicitly communicates that the measurement is precise to the ten-thousandths place.
Rule applied
Trailing zeros after a decimal point are always significant (Rule 4). See full rule →
Edge case note for 1.2300
Compare: 1.23 = 3 sig figs. 1.230 = 4 sig figs. 1.2300 = 5 sig figs. Each trailing zero adds precision.