Significant Figures Counter
Analysis Result
Significant Figures Rules
Rules for Determining Significant Figures:
Always Significant:
- Non-zero digits (1, 2, 3, 4, 5, 6, 7, 8, 9)
- Zeros between non-zero digits (1005 has 4 sig figs)
- Trailing zeros in decimal numbers (1.20 has 3 sig figs)
Never Significant:
- Leading zeros (0.0023 has 2 sig figs: 2 and 3)
- Trailing zeros in whole numbers without decimal points (1200 has 2 sig figs: 1 and 2)
Examples with Explanations:
| Number | Sig Figs | Significant Digits | Explanation |
|---|---|---|---|
| 123 | 3 | 1, 2, 3 | All non-zero digits |
| 0.00123 | 3 | 1, 2, 3 | Leading zeros don't count |
| 1.05 | 3 | 1, 0, 5 | Zero between non-zeros counts |
| 1.200 | 4 | 1, 2, 0, 0 | Trailing zeros after decimal count |
| 1200 | 2 | 1, 2 | Trailing zeros in whole number don't count |
| 1200. | 4 | 1, 2, 0, 0 | Decimal point makes trailing zeros significant |
Tip: To avoid ambiguity with trailing zeros in large numbers, use scientific notation. For example, 1.20 × 10³ clearly has 3 significant figures.