Below is a sig fig calculator (significant figures calculator) that counts significant figures or rounds numbers to a specified number of sig figs.
Sig Fig Calculator
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Using the sig fig calculator
Choose between Count Sig Figs or Round to Sig Figs mode. Enter your number and the calculator shows:
- The count of significant figures
- A visual breakdown highlighting significant digits in blue
- Decimal places count
- Scientific notation form
What are significant figures?
Significant figures are the digits in a number that carry meaningful information about its precision. The rules:
- All non-zero digits are significant
- Zeros between non-zero digits are significant (e.g., 1005 has 4 sig figs)
- Leading zeros are NOT significant (e.g., 0.0034 has 2 sig figs)
- Trailing zeros after a decimal point ARE significant (e.g., 0.00340 has 3 sig figs)
Examples
- 1234 → 4 sig figs
- 0.00340 → 3 sig figs
- 100.0 → 4 sig figs
