so I've read around forums that the max current from a RPi 3.3v GPIO pin is 50 mA, but since it is the max I don't know if I should take a resistor for 50 mA or for a lower current.


1 Answer 1


You have been misinformed.

The 50 mA is for the GPIO as a whole. (This applies to the original Pi A & B; the B+ and later (with 40 pin header), including the Pi Zero, have no such limit.)

It is generally suggested that you don't try to draw more than 16 mA from a single GPIO (although the 16 mA figure is actually how much can be drawn before the GPIO can't reliably signal a logical high).

You need to expand your question to explain what you want to do if you want a useful answer.

  • OK, but for example, if you write a simple program to turn on an led, the GPIO pin sends all of the 16mA?
    – Iliyan
    Jul 4, 2017 at 15:59
  • The GPIO will send as much as it can, which can be a lot more than 16 mA (perhaps even more than 50 mA). Normally the thing you connect will have a resistance to limit the current. In the case of a LED it has no resistance so it needs a resistor in series to prevent the LED burning out.
    – joan
    Jul 4, 2017 at 16:43

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