How it works
Round a number to a chosen number of significant figures.
Enter a number and the number of significant figures you want. The calculator uses standard base-10 rounding to shorten the number while preserving its precision to the requested digits.
Formula
Round x to n significant figures using standard rounding (half away from zero at the boundary).
x- Input number
n- Significant figures (1–15)
Examples
- 1234.5 to 3 significant figuresNumber 1234.5 · sig figs 31230
Frequently asked questions
What are significant figures?
They are the digits that carry meaning about the precision of a measurement or value.
Do leading zeros count?
No — leading zeros are placeholders and do not count as significant figures.
How to read the result
The result keeps the most meaningful leading digits and rounds the rest.
Limitations
Standard decimal rounding; no scientific-notation display on its own.
Source: Standard significant-figure rounding rules.