All non-zero digits are significant digits | |

Number | Number of Significant Digits |

3 | 1 |

2.6 | 2 |

6263.48 | 6 |

Zeroes between non-zero digits are significant digits | |

Number | Number of Significant Digits |

208 | 3 |

6.007 | 4 |

80.002 | 5 |

Zeros to the left of the first non-zero digit (leading zeros) are not significant | |

Number | Number of Significant Digits |

0.0072 | 2 |

0.0405 | 3 |

0.00000004730 | 4 |

Trailing zeros in a decimal number are significant | |

Number | Number of Significant Digits |

0.0020 | 2 |

0.00200 | 3 |

7.30 | 3 |

0.004800 | 4 |

0.00372300 | 6 |

Trailing zeros in a non-decimal number is ambiguous | |

Number | Number of Significant Digits |

28000 | 3 |

28000 | 4 |

4000000 |
2 |

300. | 3 |

Every digits in a scientific notation are significant | |

Number | Number of Significant Digits |

7x10^{4} |
1 |

8.2x10^{3} |
2 |

8.20x10^{3} |
3 |

8.200x10^{3} |
4 |

6.7381 x 10^{4} |
5 |

3.2×10^{−4} |
2 |

3.20×10^{−4} |
3 |

Example: 24.79 x 2.53 =
62.7187 The result: 62.7 has the least number of significant digits (3 significant digits)
When you 103.280 + 9.4 –
52.9872 = 59.6928 The result: 52.4 has fewest 2 decimal places |