Resistor value calculator

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Section Hand
Thanks, good information to have and a timely one at that since I was soldering resistors to 22 gauge wire yesterday.

Thanks again.


D&J RailRoad

Professor of HO
Despite the color code, I just measure it with an ohm meter to get the actual value. They do have a variance which is indicated by the last color. The cheaper the resistor, the more the variance.


Well-Known Member
Staff member
The reason I found it, I had got some pre-wired LED's with resistors and I just wanted to check one to find out what it's value was after I had contacted the wires against the tracks while powered up (NCE 5amp). I had to peel the shrink off one to see the colors. It had 5 bands, brown, black, black, violet and yellow. Found by experimentation that the yellow was the 1st band to enter. Came up with 470 ohm. The LED was quite bright (warm white) but not overly so, and holding the resistor between the fingers indicated no heating of it.


Well-Known Member
When I studied communications electronics back in the 70s they taught us a very politically incorrect way to remember the color code. I still remember it, but I will not repeat it. is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to