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Reference tables

Quick reference values used by the calculators. Manufacturer data takes precedence for production designs.

Input guide

PCB reference values — PCB reference values
Look up typical copper, laminate and mechanical values. Use the manufacturer’s datasheet for the material or part you plan to use.
Illustration only. Not to scale.

Copper weight

These are the values used by the current calculators.

Base copper	Thickness
0.25 oz	0.35 mil
0.5 oz	0.70 mil
1 oz	1.40 mil
1.5 oz	2.10 mil
2 oz	2.80 mil
2.5 oz	3.50 mil
3 oz	4.20 mil
4 oz	5.60 mil
5 oz	7.00 mil

Plating thickness

Plating	Thickness
None	0.00 mil
0.5 oz	0.70 mil
1 oz	1.40 mil
1.5 oz	2.10 mil
2 oz	2.80 mil
2.5 oz	3.50 mil
3 oz	4.20 mil

Common laminate values

Typical values only. Use the laminate datasheet for controlled impedance work.

Material	Er	Tg
FR-4, standard	4.60	130 °C
FR-4, high Tg	4.30	180 °C
Polyimide	3.40	260 °C
PTFE	2.10	260 °C
Ceramic-filled	6.15	N/A

Mechanical information

Input guide

Mechanical dimensions — Mechanical dimensions
Check the wire, drill and fastener dimensions against the datasheet before committing to a footprint.
Illustration only. Not to scale.

Typical reference values. Check the actual wire, drill and fastener datasheets for production work.

Copper wire gauge

AWG	Diameter	Resistance
10	2.588 mm	1.00 Ω / 1000 ft
12	2.053 mm	1.59 Ω / 1000 ft
14	1.628 mm	2.53 Ω / 1000 ft
16	1.291 mm	4.02 Ω / 1000 ft
18	1.024 mm	6.39 Ω / 1000 ft
20	0.812 mm	10.15 Ω / 1000 ft
22	0.644 mm	16.14 Ω / 1000 ft
24	0.511 mm	25.67 Ω / 1000 ft
26	0.405 mm	40.81 Ω / 1000 ft
28	0.321 mm	64.90 Ω / 1000 ft
30	0.255 mm	103.20 Ω / 1000 ft

Drill sizes

Size	Inches	Millimetres
#60	0.040 in	1.016 mm
#55	0.052 in	1.321 mm
#50	0.070 in	1.778 mm
#45	0.082 in	2.083 mm
#40	0.098 in	2.489 mm
#35	0.110 in	2.794 mm
#30	0.128 in	3.251 mm
1/8"	0.125 in	3.175 mm
3/16"	0.188 in	4.775 mm
1/4"	0.250 in	6.350 mm

Metric screw threads

Size	Major diameter
M2 × 0.4	2.00 mm
M2.5 × 0.45	2.50 mm
M3 × 0.5	3.00 mm
M4 × 0.7	4.00 mm
M5 × 0.8	5.00 mm
M6 × 1.0	6.00 mm
M8 × 1.25	8.00 mm