Significant Figure Rounding Calculator
Format a finite number to a specified count of significant digits.
Your result
MATHEnter your values and select calculate.
On this page How it works & practical examples
How to use the Significant Figure Rounding Calculator
Enter the number and desired significant-digit count. Scientific notation is retained when precision formatting uses it, so trailing retained zeros remain visible.
The calculation
Worked example
12,345 to three significant digits displays 1.23e+4, representing 12,300.
Assumptions and limits
JavaScript decimal formatting operates on binary floating-point inputs. Exact decimal ties can reflect representation effects; this tool does not infer measurement uncertainty from digit count.
Common questions
Which inputs should I use?
Enter the number and desired significant-digit count. Scientific notation is retained when precision formatting uses it, so trailing retained zeros remain visible.
What does the result exclude?
JavaScript decimal formatting operates on binary floating-point inputs. Exact decimal ties can reflect representation effects; this tool does not infer measurement uncertainty from digit count.