Convert between oz, µm, mil, and mm for PCB copper weight
Click any result to use it as input
| Weight | oz/ft² | µm | mil | mm |
|---|---|---|---|---|
| 1/4 oz (Ultra-thin) | 0.25 | 8.8 | 0.34 | 0.009 |
| 1/2 oz (Standard signal) | 0.5 | 17.5 | 0.69 | 0.018 |
| 1 oz (Most common) | 1 | 35.0 | 1.37 | 0.035 |
| 2 oz (Power/high current) | 2 | 70.0 | 2.74 | 0.070 |
| 3 oz (Heavy copper) | 3 | 105.0 | 4.11 | 0.105 |
| 4 oz (Heavy copper) | 4 | 140.0 | 5.48 | 0.140 |
| 6 oz (Extreme power) | 6 | 210.0 | 8.22 | 0.210 |
Click any row to use as input
1 oz copper refers to the weight of copper spread over 1 square foot, which equals 35 µm thickness.
This is the most common copper weight for standard PCBs, suitable for most signal traces and moderate current applications.
Copper thickness directly affects current carrying capacity, heat dissipation, and impedance. Choosing the right copper weight is essential for reliable PCB performance.
Heavier copper requires adjusted design rules for reliable manufacturing: