长度是一个基本的物理量，可测量两个点之间的距离。它是国际单元（SI）中的七个基本单元之一，仪表（m）是其基本单元。
1 in = 8.2307e-19 pc
1 pc = 1,214,960,629,921,259,800 in
例子:
将15 英寸转换为parsec：
15 in = 1.2346e-17 pc
| 英寸 | parsec |
|---|---|
| 0.01 in | 8.2307e-21 pc |
| 0.1 in | 8.2307e-20 pc |
| 1 in | 8.2307e-19 pc |
| 2 in | 1.6461e-18 pc |
| 3 in | 2.4692e-18 pc |
| 5 in | 4.1154e-18 pc |
| 10 in | 8.2307e-18 pc |
| 20 in | 1.6461e-17 pc |
| 30 in | 2.4692e-17 pc |
| 40 in | 3.2923e-17 pc |
| 50 in | 4.1154e-17 pc |
| 60 in | 4.9384e-17 pc |
| 70 in | 5.7615e-17 pc |
| 80 in | 6.5846e-17 pc |
| 90 in | 7.4076e-17 pc |
| 100 in | 8.2307e-17 pc |
| 250 in | 2.0577e-16 pc |
| 500 in | 4.1154e-16 pc |
| 750 in | 6.1730e-16 pc |
| 1000 in | 8.2307e-16 pc |
| 10000 in | 8.2307e-15 pc |
| 100000 in | 8.2307e-14 pc |
规则