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Trace Width vs Length Inductance Table for PCB Traces

I need to know the inductance of the traces I’m creating.  It’s too slow to use the inductance calculator at All About Circuits.   Unfortunately, the equation has any given variable on both the numerator and the denominator.  I refuse to invest the brainpower to develop a rule of thumb, so I’m resorting to a table.  I swiped their equation and tossed in typical values for trace widths  I used in Python.

I wouldn’t use this for anything hyper serious, but if I’m forced to make a 4″ trace, I can quickly see that doubling the width from 0.5mm to 1mm saves me 12nH.

The intuition to be gained from this (and this is probably not a shocker) is that keeping lengths down is a HUGE deal for reducing the inductance of traces.  Trace width is a little more interesting.   In terms of %, you get much better benefit for wide traces at short distances.  At 0.02″, inductance is reduced from 0.171 to 0.075 when switching from 0.01″ traces to outrageous 0.118″ traces.    At distances ~4″,  you go from 136.978nH with tiny traces to 93nH with enormous traces.

I’m using the JLC2313 stackup so the height of these calculations (distance from trace to ground plane) is 0.1mm.

Length: 0.02 in
Width: 0.01 in ( 0.25 mm ) Inductance: 0.171 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 0.128 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 0.104 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 0.09 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 0.08 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 0.075 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 0.075 nH

Length: 0.039 in
Width: 0.01 in ( 0.25 mm ) Inductance: 0.464 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 0.368 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 0.309 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 0.269 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 0.239 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 0.216 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 0.151 nH

Length: 0.197 in
Width: 0.01 in ( 0.25 mm ) Inductance: 3.868 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 3.34 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 3.003 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 2.756 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 2.563 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 2.404 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 1.81 nH

Length: 0.394 in
Width: 0.01 in ( 0.25 mm ) Inductance: 9.107 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 8.04 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 7.354 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 6.85 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 6.452 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 6.123 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 4.867 nH

Length: 1 in
Width: 0.01 in ( 0.25 mm ) Inductance: 27.842 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 25.116 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 23.357 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 22.059 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 21.03 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 20.178 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 16.885 nH

Length: 1.969 in
Width: 0.01 in ( 0.25 mm ) Inductance: 61.566 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 56.187 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 52.715 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 50.148 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 48.111 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 46.423 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 39.876 nH

Length: 3.937 in
Width: 0.01 in ( 0.25 mm ) Inductance: 136.978 nH
Width: 0.02 in ( 0.51 mm ) Inductance: 126.21 nH
Width: 0.03 in ( 0.76 mm ) Inductance: 119.255 nH
Width: 0.039 in ( 0.99 mm ) Inductance: 114.109 nH
Width: 0.049 in ( 1.24 mm ) Inductance: 110.025 nH
Width: 0.059 in ( 1.5 mm ) Inductance: 106.638 nH
Width: 0.118 in ( 3.0 mm ) Inductance: 93.477 nH

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