Rounding values to the Desired Number of Significant Figures Calculator

[ 14 Votes ]

TheRounding values to the Desired Number of Significant Figures Calculator will:

  1. Round a given value to the desired number of significant figures

Rounding values to the Desired Number of Significant Figures Calculator
Rounding Values Calculator Results (detailed calculations and formula below)
Rounding Values Calculator Input Values
Number to round (x) =
Significant Figures (p) =

Please note that the formula for each calculation along with detailed calculations is shown further below this page. As you enter the specific factors of each rounding values calculation, the Rounding Values Calculator will automatically calculate the results and update the formula elements with each element of the rounding values calculation. You can then email or print this rounding values calculation as required for later use.

We hope you found the Rounding Values Calculator useful, if you did, we kindly request that you rate this calculator and, if you have time, share to your favourite social network. This allows us to allocate future resource and keep these Math calculators and educational material free for all to use across the globe.

[ 14 Votes ]
Rounding Values. This image shows the properties and rounding values formula for the Rounding Values

Theoretical description

Significant figures are all digits that add to the meaning of the overall value of the number. To prevent repeating figures that aren't significant, numbers are often rounded. One must be careful not to lose precision when rounding. Often, the goal of rounding numbers is just to simplify them.

There are five rules to find the correct number of significant figures in a given value. They are:

  1. Leading zeroes in a decimal number are not counted as significant.
  2. Trailing zeroes in a whole number are not counted as significant.
  3. Trailing zeroes in a decimal number are counted as significant.
  4. Zeroes in-between two non-zero digits are counted as significant.
  5. All non-zero digits in both whole and non-whole numbers are counted as significant.

For example, 153,2917 expressed in 1 s.f. becomes 200, in 2 s.f. becomes 150, in 3 s.f. becomes 153, in 4 s.f. becomes 153.3, in 5 s.f. becomes 153.29 and in 6 s.f. becomes 153.292.

Remark! Sometimes, it is not possible to round the number to the given number of significant figures. For example, the number 103 cannot be rounded to 2 s.f because when rounded to the nearest ten and hundred, it becomes 100, which is a number with 1 s.f. In this case, the calculator will show a warning message stating "rounding to x significant figures is not possible" and a horizontal line is displayed at the top of the second zero, i.e.

103 ≈ 100 to 2 s.f.

This significant figures calculator counts how many non-zero digits (including zeroes in-between two non-zero digits) are in the original number starting from the left, and rounds the Input x to p significant figures.

All the other digits on the right of the original number become zero (in integers) or disappear (in decimal numbers).

Approximations Math Tutorials associated with the Rounding Values Calculator

The following Math tutorials are provided within the Approximations section of our Free Math Tutorials. Each Approximations tutorial includes detailed Approximations formula and example of how to calculate and resolve specific Approximations questions and problems. At the end of each Approximations tutorial you will find Approximations revision questions with a hidden answer that reveal when clicked. This allows you to learn about Approximations and test your knowledge of Math by answering the revision questions on Approximations.