It depends on the Vmax of each led....
Some led's have a higher/lower Vmax than others, it depends on
manufacture/color, or both.... Figure 20ma to be safe, and an
average of 3.0v per led...

You should be able to figure it from there...

Rich wrote:
I have some assorted led's, lots of colors.
What value resister do I add in the circuit with 12 VDC?



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Bob N9LVU