JLCPCB Copper Weight (Thickness) Guide

Definition:

Copper weight (or thickness) in PCB manufacturing is measured in ounces (oz).

● 1oz copper = copper thickness of 35 µm, which is the thickness of 1 oz of copper spread over 1 ft².

PCB Type	Layer	Available Copper Weight	Notes
FR4 PCB	Outer layer	1oz, 2oz (standard)	Heavier options for 2-layer only
	2-layer FR4 only	2.5oz, 3.5oz, 4.5oz	Special high-current designs
	Inner layer	0.5oz (default), 1oz, 2oz	Availability depends on total layers and overall thickness
FPC (Flexible PCB)	Inner & Outer layers	1/3oz, 0.5oz, 1oz	1/3oz used for ultra-thin flexibility

⚠️ Always refer to the actual online order page for current availability and pricing.

Copper Weight	Applicable PCB Type	Min. Trace Width / Space
0.5oz or 1oz	1–2 layers FR4	0.10 mm (4 mil)
0.5oz or 1oz	≥ 4 layers FR4	0.09 mm (3.5 mil); 3 mil available with extra cost
2oz	Any layer FR4	0.16 mm (6.5 mil)
2.5oz	2-layer FR4	0.20 mm (8 mil)
3.5oz	2-layer FR4	0.25 mm (10 mil)
4.5oz	2-layer FR4	0.30 mm (12 mil)
0.33oz	FPC	0.076 mm (3 mil); absolute limit 2 mil, avoid if possible
0.5oz	FPC	0.09 mm (3.5 mil)
1oz	FPC	0.10 mm (4 mil)

Last updated on Nov 21, 2025