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PCB Copper Weight Reference

Kupfergewicht0.5 · 1 · 2 · 3 · 4 · 6 oz/ft²
Dicke des Kupfers17.5 · 35 · 70 · 105 · 140 · 210 μm
1 oz/ft²35 μm = 1.378 mil = 0.035 mm

Copper weight (oz/ft²) to thickness conversion table with current carrying capacity for PCB trace design.

Conversion Formula

Weight to Thickness

1 oz/ft2 = 35 um = 1.37795 mil

General Formula

thickness (um) = weight (oz) x 35

Copper Weight Specifications

6 Zeilen

Copper Weight Specifications
0.5 oz/ft²17.50.6890.01751.2 A
1 oz/ft²351.3780.03502 A
2 oz/ft²702.7560.07003.5 A
3 oz/ft²1054.1340.10504.8 A
4 oz/ft²1405.5120.14006 A
6 oz/ft²2108.2680.21008.2 A

* Current capacity for 1mm trace width, external layer, 10C temperature rise (IPC-2221)

Current Carrying Capacity (IPC-2221)

External layer, 10C temperature rise above ambient. Internal layers carry approximately 50% of these values.

6 Zeilen

Current Carrying Capacity (IPC-2221)
0.5 oz/ft²1.2 A1.9 A2.5 A
1 oz/ft²2 A3.2 A4.2 A
2 oz/ft²3.5 A5.6 A7.4 A
3 oz/ft²4.8 A7.7 A10.2 A
4 oz/ft²6 A9.6 A12.7 A
6 oz/ft²8.2 A13.1 A17.4 A

Applications by Copper Weight

0.5 oz/ft2(17.5 um / 0.69 mil)
  • ->Fine-pitch BGA routing
  • ->High-density interconnect (HDI) boards
  • ->Smartphone and tablet PCBs
  • ->Inner layers in multilayer boards

Half-ounce copper is standard for HDI and fine-pitch designs. Lower current capacity limits use in power applications. Often paired with 1 oz outer layers.

1 oz/ft2(35 um / 1.38 mil)
  • ->General-purpose digital circuits
  • ->Consumer electronics
  • ->Signal routing layers
  • ->Standard commercial PCBs

Most common copper weight for general PCB fabrication. Good balance of current capacity, cost, and manufacturability. Standard baseline for IPC-2221 calculations.

2 oz/ft2(70 um / 2.76 mil)
  • ->Power distribution layers
  • ->Motor drivers
  • ->LED lighting boards
  • ->Automotive electronics
  • ->Industrial control systems

Double the current capacity of 1 oz copper. Common choice for power planes and high-current traces. Increases board cost by ~20-30%. May require adjusted trace/space rules.

3 oz/ft2(105 um / 4.13 mil)
  • ->High-power DC-DC converters
  • ->Battery management systems (BMS)
  • ->EV/HEV power electronics
  • ->Welding equipment

Heavy copper for demanding power applications. Requires special fabrication capabilities. Minimum trace/space typically 8-10 mil. Often combined with thinner signal layers.

4 oz/ft2(140 um / 5.51 mil)
  • ->Power supply boards
  • ->Busbar replacement
  • ->High-current motor controllers
  • ->Renewable energy inverters

Heavy copper requiring specialty PCB fabrication. Not all fabs support 4 oz+. Expect longer lead times and higher costs. May need edge plating for thermal relief.

6 oz/ft2(210 um / 8.27 mil)
  • ->Extreme power applications
  • ->Planar transformers
  • ->High-current busbars on PCB
  • ->Power conversion equipment

Ultra-heavy copper for extreme power requirements. Very few fabs can process 6 oz+. Often used with embedded busbars or coin insertion for thermal management.

Verwandte Rechner

Trace Width

Calculate minimum PCB trace width for current capacity per IPC-2221 and IPC-2152’s conservative Figure 5-1. Get resistance, voltage drop, and power dissipation at the width you draw. Free, instant results.

Trace Resistance

Calculate PCB copper trace DC resistance from width, length, thickness, and temperature. Get sheet resistance and temp coefficient. Free, instant results.

Via Calculator

Calculate PCB via impedance, capacitance, inductance, and current capacity. Get aspect ratio and DFM warnings for through-hole and blind vias. Free, instant results.

Controlled Z

Calculate characteristic impedance for surface microstrip, embedded microstrip, and stripline PCB traces. Get Z0, effective Er, and target trace width. Free, instant results.