Significant Figures Calculator

Perform calculations with the correct number of significant figures and show the work.


To perform a calculation, simply enter your mathematical expression and press Solve.

The result along with the steps taken to reach it will appear above.

The following sig fig rules are used:

  • Addition (+) and subtraction (-) round by the least number of decimals.
  • Multiplication (* or ×) and division (/ or ÷) round by the least number of significant figures.
  • Logarithm (log, ln) uses the input's number of significant figures as the result's number of decimals.
  • Antilogarithm (n^x.y) uses the power's number of decimals (mantissa) as the result's number of significant figures.
  • Exponentiation (n^x) only rounds by the significant figures in the base.
  • To count trailing zeros, add a decimal point at the end (e.g. 1000.) or use scientific notation (e.g. 1.000 × 10^3 or 1.000e3).
  • Zeros have all their digits counted as significant (e.g. 0 = 1, 0.00 = 3).
  • Rounds when appropriate, after parentheses, and on the final step.

How To Perform Sig Fig Calculations

Read our article on sig fig rules.

You can also ask for help in our forums.