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Sig Fig Calculator – Accurate Significant Figures Tool
The Significant Figures Calculator helps you round numbers correctly based on the number of significant digits (also called sig figs). It's essential in science, engineering, and math to express precision accurately.
How to Use the Significant Figures Calculator
To use the tool, enter:
- A number (e.g. 0.004567, 123000)
- The number of significant figures you want to round to
- (Optional) Choose operation: Addition, Subtraction, Multiplication, Division
The result will display the number rounded according to sig fig rules and scientific notation if needed.
What Are Significant Figures?
Significant figures are the digits in a number that carry meaning for precision:
- All non-zero digits are significant
- Zeros between non-zero digits are significant
- Leading zeros are not significant
- Trailing zeros are significant only if there's a decimal point
Examples
- 123.45 rounded to 3 sig figs → 123
- 0.004567 rounded to 2 sig figs → 0.0046
- 1000 rounded to 2 sig figs → 1.0 × 10³
Common Use Cases
- Scientific experiments and lab reports
- Engineering calculations with tolerances
- Rounding in chemistry or physics formulas
- Accurate rounding in standardized exams
- Maintaining consistency in published results
Why Use a Significant Figures Calculator?
Rounding incorrectly can drastically change the interpretation of data in technical fields. This tool ensures your answers are rounded properly according to sig fig rules, boosting accuracy and credibility.
Frequently Asked Questions (FAQs)
Is 0.0045 one or two significant figures?
Two. The leading zeros don't count, but "4" and "5" are significant.
What are sig fig rules for multiplication?
The result should have the same number of sig figs as the factor with the fewest sig figs.
What about addition and subtraction?
Round to the least number of decimal places, not significant figures.
What’s the difference between decimal places and sig figs?
Decimal places count digits after the point; sig figs count all meaningful digits starting with the first non-zero.
Can I round to scientific notation?
Yes. The calculator supports scientific notation for large or very small numbers.
Related tools: Rounding Calculator.