How to Calculate Significant Figures
What is Significant Figures?
Significant figures (sig figs) indicate the precision of a measurement. They include all certain digits plus one estimated digit. Leading zeros are never significant; trailing zeros after a decimal point are significant. The rules determine how many digits to keep after arithmetic operations.
Step-by-Step Guide
- 1Counting sig figs: ignore leading zeros, count everything else
- 2Trailing zeros with decimal point are significant: 3.00 has 3 sig figs
- 3Trailing zeros without decimal are ambiguous: 300 could be 1, 2, or 3 sig figs
- 4Addition/subtraction: round to the least number of DECIMAL PLACES
- 5Multiplication/division: round to the least number of SIG FIGS
Worked Examples
Frequently Asked Questions
What is Significant Figures?
Significant figures (sig figs) indicate the precision of a measurement. They include all certain digits plus one estimated digit
How accurate is the Significant Figures calculator?
The calculator uses the standard published formula for significant figures. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Significant Figures calculator use?
This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Significant Figures calculator use?
The calculator applies the standard formula for this type of calculation. See the 'How It Works' steps above for the detailed formula breakdown.
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