Led question

[caraudioguy2100]

If I wanna hook up an led to the 12 volt power line of an amp say the remote turn on wire what value resistor would I need ?

It’s just a small led like the ones used in amps for the power light

 

[Perry Babin]

There's a calculator on the following page.
Light Emitting Diodes (LED)

The value isn't critical to the LED. Lower value drives more current through it and can make it run hot and die an early death. On 12v a 1k resistor is generally perfectly fine for red, green, blue and amber LEDs.