As many others im getting a Zero W for PiHole and i would like to power it using the usb-port of my wifi router. However, im concerned about undervoltage. I read the Zero W wants 1,2A, but usb 2.0 only has about 500mA or so. Without a screen i wouldnt recognize the Pi getting undervoltaged.

Does it really consume that much? The Zero wont get any active coolers, displays or leds.

  • 1
    I read the Zero W wants 1,2A ... please provide a link to the page where you read that
    – jsotola
    Jan 19, 2022 at 22:48

1 Answer 1


There is a lot ill-informed opinion about Pi. See Raspberry Pi Power Limitations. This has links to Typical Power Requirements which shows Typical bare-board active current consumption 150mA.

If you are using WiFi it will certainly be more, but a stand alone (i.e. no peripherals) Pi Zero W should run on 500mA.

Whether your Fritz!Box can supply this is unknown. Strictly USB should only supply 150mA without negotiation (which the Pi can't do) but many (most?) USB devices ignore this.

You asked if it is "safe" - certainly there is no danger, it will either work or not.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.