First things first – Inches fractions & decimals.
The table below shows Imperial fraction to decimal conversions.
| Imperial | ||
| Fraction | Decimal | Rounded To |
| 1 | 1.000 | 1 |
| 1/2 | 0.500 | 0.5 |
| 1/4 | 0.250 | 0.25 |
| 1/8 | 0.125 | 0.125 |
| 1/16 | 0.0625 | 0.062 |
| 1/32 | 0.03125 | 0.031 |
| 1/64 | 0.015625 | 0.016 |
Think Thousandths (Thou’s) for example 0.125 would be 125 thou’
The table below shows Imperial fraction & decimal to Metric conversions.
| Imperial – Metric | ||
| Fraction | mm | Rounded To |
| 1 | 25.40 | 25.4 |
| 1/2 | 12.70 | 12.7 |
| 1/4 | 6.35 | 6.35 |
| 1/8 | 3.175 | 3.18 |
| 1/16 | 1.5875 | 1.6 |
| 1/32 | 0.79375 | 0.8 |
| 1/64 | 0.396875 | 0.4 |
| Decimal | mm | Rounded To |
| 1 | 25.40 | 25.4 |
| 0.100 | 2.54 | 2.54 |
| 0.010 | 0.254 | 0.25 |
| 0.001 | 0.0254 | 0.02 |