Signifikante-Stellen-Rechner — Formel

## Significant Figures

### Rules for Counting Significant Figures

1. All nonzero digits are significant (123 has 3 sig figs)
2. Zeros between nonzero digits are significant (102 has 3)
3. Leading zeros are NOT significant (0.0045 has 2)
4. Trailing zeros after a decimal point ARE significant (2.50 has 3)
5. Trailing zeros without a decimal point are ambiguous (1500 could be 2, 3, or 4)

### Rounding to n Significant Figures

1. Find the first significant digit
2. Count n digits from there
3. Round at that position